What is sptd.sys? Is sptd.sys spyware or a virus?

How to fix sptd.sys related problems?
1. Run Security Task Manager to check your sptd process
2. Run Windows Repair Tool to repair sptd.sys related Windows Errors
3. Run MalwareBytes to remove persistent malware

Process name: SCSI Pass-Through Direct Host

Product: SCSI Pass Through Direct

Support: Help link [1][2]   Update link [1][2]   Uninstall tool  

Company: Duplex Secure Ltd.

File: sptd.sys

SCSI Pass-Through Direct (SPTD) is a proprietary device driver and application programmer interface (API) by Duplex Secure, Ltd., in London, UK. It is available as a replacement for Microsoft's older SCSI Pass-Through Interface (SPTI), but is unrelated to it. It provides a new method of access to storage devices that are accessed by Microsoft Windows operating systems through the Small Computer System Interface (SCSI) bus, such as hard disks, CDs, and DVDs, including BluRay. Its latest stable release is 1.86 as of November 2013. It is only supported by Microsoft Windows operating systems, level 2000 and above, (XP, Vista, 7, and 8). Duplex Secure is listed as a technology partner in the StarBurn Technical Alliance, indicating a committed link to promoting deployment of, and being interoperable with, StarBurn Software's CD/DVD/BluRay burning applications. SPTD may therefore be present on systems using hardware or software from StarBurn or any of its alliance partners. Alcohol 120% uses SPTD and AlcoholSoft is also listed in this Alliance. DaemonTools and CoreXWare's Power Archiver Pro 2010 also use it, although the latter has a configurable option to turn SPTD off. CoreXWare said internal testing showed 20% better optical drive performance than SCSI Pass-Through Interface.

Users of kernel-mode debugging programs, such as Microsoft's WinDbg and their other command-line debuggers, should be aware that SPTD is known to be incompatible with kernel-mode debugging. If you want a detailed security rating about your sptd.sys (and all other running background processes) read the following user opinions, and download the free trial version of Security Task Manager. www.neuber.com/taskmanager/process/sptd.sys.html 

Note: Any malware can be named anything - so you should check where the files of the running processes are located on your disk. If a "non-Microsoft" .exe file is located in the C:\Windows or C:\Windows\System32 folder, then there is a high risk for a virus, spyware, trojan or worm infection! Check it out!

Click to Run a Free Scan for sptd.sys related errors

Users Opinions

Average user rating of sptd.sys: based on 179 votes. Read also the 144 reviews.

  • 7835 users ask for this file. 72 users rated it as not dangerous. 13 users rated it as not so dangerous. 36 users rated it as neutral. 38 users rated it as little bit dangerous. 20 users rated it as dangerous. 11 users didn't rate it ("don't know").

All comments about sptd.sys:
Installed with Daemon Tools V4.00 - Scsi Pass Through Direct (sptd.sys) driver  See also: Link Rod Dines
SCSI pass-through driver, for me it came with daemon-tools
Daemon Tools Driver  See also: Link Shay
Daemon tools 4.0 or something T
Deamon Tools
This is a part of Daemon Tools software  See also: Link mspeedo
A driver for DAEMON Tools Virtual Drive Manager. Configured to be the very first driver to load when system starts; may cause instability. Leon
Driver used by the CD Rom emulation program, Daemon Tools Version 4. There have been some reports of problems with this driver.
SCSI Pass Through - Comes with Alochol Jeremy
Came with Daemon Tools. Not dangerous, but can't boot when SATA and ATA drives are installed.  See also: Link Task514
Daemon Tools Phil
comes with daemon tools and alcohol. The company is duplex secure (www.duplexsecure.com).. It is supposedly an interface system that prevents rootkits from working etc (however it is a bit strange in itself, as it blocks registry keys, file access and other things), so it is hardly 'harmless'  See also: Link w. cossey
I make extensive use of Daemon Tools, so I absolutely couldn't miss it. Geert Porteman
If you have an UNMOUNTABLE_BOOT_VOLUME error, and try to boot to safe mode, SPTD.sys freezes the system when it tries to load. sneako
Along with Daemon tools v4 power
This is something you need if you are running Daemon Tools. If you have problems starting Windows, then you have to upgrade the driver. Get the newest one from the link.  See also: Link Max
it cause BSODs on most pc - reinnstal system and clear the bootsector
Daemon Tool 4.03's driver  See also: Link alextooter
Daemon Tools swiebertje
SCSI Pass Through Direct used for many virtual drive software tools  See also: Link Nick Price
SCSI Pass Thru Direct driver for Daemon tools or Alcohol 120% Jon
I dont have daemon tools installed, and i got this file. i use alcohol Dt
DAEMON Tools is not dangerous... it does have optional adware though... anger2headshot
SCSI Pass Through Direct layer (http://www.duplexsecure.com/). Comes with Alcohol software or Daemon Tools.
i have a vista and in bsod i see message sptd.sys i don't have daemon tools i have alcohol 120% hmm maybe is system file ? MarcinPoland
Daemon Tools 4  See also: Link Phantom
file for Alcohol120% Alex Ershov
Loads with Alcohol 120%. More info & Uninstall see link  See also: Link scoobie
Driver for DAEMON Tools. Hides part of the registry. Hooks registry api. Richard
Also installed by Alcohol 120% Scree
For me, after updating my Win Xp Pro, i was unable to boot past the splash screen...after some trial and error in safe mode..renaming this file..allowed me to login to Windows. Brian
As above with Daemon Tools 4.x.x driver aergaroth
SCSI Pass-Through Direct, similar to ASPI or SPTI but more features. Not malware. To uninstall, simply download the setup file from the link, and in the dialog that shows, click "Uninstall". SPTD is required by Daemon Tools and other software making use of virtual optical drives. It is a much safer method of creating virtual drives then just assigning a drive letter to a directory, as the virtual drive software has direct control over the drive. A rootkit or other malicious program could simply change files to compromise a system, with SPTD, malicious software is locked out of the loop.  See also: Link Gordon Pettey
Let my system freeze during startup. A real pain in the a**. Warrior
Installs with a darmon tools when windows boots bribot
Causes safe mode to freeze...normal mode 2 BSOD. Delete the file. Circlestrafe
would not allow system to boot in safe mode. rowdy
Alcohol/DAEMON related. Completly harmless. As with all programs, it may be unstable in certain systems
Could be from Daemon Tools or Alcohol
think it's essential if they don't have to logon safemode, now i'm having a problem with user admin and need to logon in safemode, i tried many think, many way to solve this problem but ......dfs#*@#*99. anyway it's also very good when we want to play game or anything else with and virtual driver (made by daemon tool, alcohol 120 ...) hoang
It causes Rootkit Revealer alarm! There are some registry entries hidden. hank
Alcohol 120% and Daemon Tools virtual drive driver. Disel
It comes with a number of Drive Emulation and Disc Mastering software, including Daemon Tools and Alcohol (120% and 52%). Duplex Secure claims sptd.sys is a security benefit. But the software itself acts like a rootkit. And, while it has nothing to do with networks, it somehow disrupts network connections. When the original software (Alcohol, for example) is removed this driver stays in place. It is particularly hard to remove (a number of abnormally protected registry keys + the driver file). Angry User
Daemon Tools Pytha
Daemon tools. up to ver 1.55 still causes occasional boot problems Steve
Installed with Daemon Tools  See also: Link Chris C
This device driver causes USB flash drives, Garmin flash drives from loading and mapping proper drive letters. I renamed it and my computer could see my camera, flash drive and Garmin GPS. Squirrelly
 See also: Link georgi
prevents windows from starting in safe mode; prevents windows from closing down Criminalist
daemon tool. no information on it, bujt required for daemon tool Reign-of-undead
Deamon Tools Don´t matter
Part of Daemon Tools Franz2000
alcohol 120% vuze
SCSI Pass Through Driver, comes with many virtual drives. I haven't have any problems with this ever.
I was having problems with USB flash drives, and my camera not being given a drive letter when I connected them. Even using disk management to assign a drive letter would not result in the drive showing up in Windows Explorer. Taking advice from an Internet tech site, I renamed sptd.sys, and the problems with the USB drives disappeared. I have had daemon tools installed i nthe past, but had uninstalled them some time ago.  See also: Link PeterTB
Its caused my system to have an unmountable boot volume, safe mode to freeze, and setup disks to repair to freeze. Basically I cant get to a command prompt to remove the !@#$(# thing and so my system is totally screwed and I have no idea what to do! Extremely Angry User
Sptd.sys i found it EVEN with alcohol and Daemon tools not installed! Cris
Installed with DVD Rom Emulation Software StarWind Burner  See also: Link Ben
I had this sptd.sys file on my computer, which would not let AV program update or install. I restored system of earlier date, and simply deleted this file. Sunil
Its stopping me from logging in safemode which is CRUCIAL for me to fix an antiwvirus. so i m really hating thiss file right now Virus Victim
Caused a mayjor root kill whilst remoted into a client, unable to sort Austin Powers
CDRom Emulation Driver. Used by Daemon tools/Alcohol and possibly others.  See also: Link Trevor
some info available at daemon tools forum  See also: Link Gts
Sophos Anti-Rootkit found it as a rootkit. I believe it is part of the Alcohol 120% that Installed though. I hope its not bad! nat
SPTD.SYS (Duplex Secure Ltd. built by: WinDDK - SCSI Pass Through Direct Host - [Digital Signature:/Duplex Secure Ltd /Monday, 23 March 2009 4:38:51 PM] Obviously part of the setup for mobo's or SCSI third party introduced purposely!). Dazz
Es tut keinem weh... Thorsten
Comes with Daemon tools, ImgBurn doesn't like it Ralph
C:\WINDOWS\system32\drivers\sptd.sys... file could not be scanned! J
It comes bundled with ISOMagic I believe this is a dangerous file. Why does the file fail to disclose its identifying producer? Why so many inconsistencies in file sizes, and the fact it sets of RootKit Reveal? Too many question and not supporting evidence of value. Thats got virus / spyware / Rootkit written all over it !! !! !! RJ
Caused a BSOD and gave me a 0x0000007e error.. Couldn't get into safe mode without pressing esc to cancel it loading..Adware picked it up and removed it. Everything works now! Don't have alcohol or daemon installed.. Steve
It's from Daemon tools and alchohol 120%. This little bugger is a time bomb. It should work fine with those programs but for some such as myself it will malfunction and crash windows. Expect a BSOD from then on whenever loading normally. On top of that it can cause safe mode to freeze up. Expect a lot of trouble when this software goes bad and make sure to delete it if you don't need it. Johan
WinXP.SP2 during sfafe mode boot, when the drivers are scrolling on the screen, I get the option to NOT load sptd.sys. This might help those that can't boot to safe mode. I can get to safe mode, but I get a black screen after the WinXP splash screen. My sys was fine until I swapped cases yesterday. Gonna try disabling it, then install new version from Duplex Security - newest version:  See also: Link GeoNOregon
DaemonTools driver. Safe on most systems, but may cause instability. Use at your own risk. Jenny
SCSI Pass Through Direct Layer (duplex secure) - uninstall with:  See also: Link kaminariko
Caused machine to boot slowly. Culprit with this file. Jeff
It appears that people with Windows Media Center edition are having issues with this file, as it occasionally keeps your computer from booting. This is my current problem, and I haven't found a resolution yet. There's a chance it's been hijacked by malware, but on the surface it's not malware in and of itself. natedsaint
Not allow windows to start niether normal or in a safe mode delete the file to avoid blue screen in windows boot Allan
As others have said, it's a Scsi Pass Through Direct driver. Any crashes, BSOD, lockouts etc are a combination of system instabilities and with everyones computer set up differently, with different software installed, blaming just one driver can be misleading. I have run Daemon tools for many years,on different Operating Systems and different computers with no problems. And to the User that wrote "Its caused my system to have an unmountable boot volume, safe mode to freeze, and setup disks to repair to freeze. Basically I cant get to a command prompt" get Hirens Boot disc.Link below  See also: Link Phrozen
Can be cleverly altered to cause system to be stuck in reboot loop. Thankfully deleting can stop this problem John Smith
SPTD stands for SCSI Pass Through Direct layer. Basically SPTD is similar to other access layers used by other programs who provide access to storage devices but it has a lot more features that make this interface unique.  See also: Link josy
Cause: Windows Blue Screen, SOLUTION: delete alcohol and sptd.sys. Problem solved! xcape
When I boot in Safe mode sptd ask me: "If you want ot run sptd.sys press enter", I'm not pressed enter, and the machine perfect booted. Cool if AI
Okay everyone, I had the same probs as you. Here is what I have done so far. Booting problems: If option for sage mode comes up. It will ask if you want to start without sptd.sys. Start without it. You will then be able to start your computer in safemode. After that goto C:\WINDOWS\system32\drivers and locate Sptd.sys and rename it. Then goto install/Remove programs and remove any DVD Rom emulation software that or burning software that you installed. That sould fix the problem. Evidently when these programers had created these programs the got lazy and did not think it all the way through. Ronathon01
Größe: 721.904 bzw 724992 Bytes J.F.K.
XP system crashing during boot - rebooting too fast to check blue screen error message. When safe mode chosen, was asked if wanted to load SPTD.SYS. Loading crashed again. Not loading booted in safe mode. Renamed SPTD.SYS to SPTD.OLD. Normal boot worked now. Daemon tools error message after boot. Pagla
alcohol 120 Scott
It keeps appearing on my system, even if I delete it. I DO NOT HAVE daemon tools or Alcohol or StarWind Burner (the named programs) so there is more to it than most people think. My antivirus (Avira) says the file is locked and cannot be scanned for viruses. SandorTK
Comes with Alcool 120% and Deamon Tools. Can't boot in safe mode with it. Yvan Dubois
I have windows media center and I wish I'd found this post ages ago! I do have alcohol 120 installed. This file kept both my desktop and laptop from booting, and I ended up reformatting both hard drives and losing lots of data just a few months ago. when this happened again just last week, I decided to press ESC when STPD.SYS was loading. This allowed me to boot into safe mode (first, select Safe Mode with Networking, then when the system loads, watch the screen until you get a message to press ESC to stop loading STPD.SYS, and then press Esc, you'll be able to boot!) now can start up norm jennifer
vista event viewer shows "Driver detected an internal error in its data structures for ." and after second i got bsod. piiters
Have Daemon Tools installed, wasn't causing any problems until recently when running a potentially unwanted file from the internet. Got the blue screen then a restart and another. Works in Safe Mode, however, also works perfectly fine in Debugging Mode, accessible with F8 during startup. Last known good configuration should have worked, but didn't. This may only be me, but I would suggest trying Debugging Mode to run Windows perfectly fine. Also, when starting Safe Mode, it questions if you would like to run SPTD, just don't do anything. It won't load it and you can run Safe Mode fine. Sam
Did a new format with XP then added SP3. Installed a/v and firewall. Then programs I normally use. Installed Active ISO burner, that's when the problems began. Slow boot, no boot, locking after displaying desktop but no icons or taskbar. Somehow got into safe mode and used system restore to a point before Active ISO was installed. Now all is fine. Will not use this product. From research it seems SPTD Duplex is the culprit. Lars
Daemon Tools
Necessary for CDRom Drive Emulation. Is known for causing BSOD and failed boot attempts. Remove from your system if not using CDRom emulation. ЯΛΛB
It's part of either Daemon Tools or Alcohol 120%. It's not harmful but will cause instablity on some systems. I'm running Windows 7 64-bit and all is fine.
Install with Alcohol 120%  See also: Link Ram Agarwal
After installation i couldnt boot my system anymore. It can be very dangerous. Michel
In some cases it prevents XP Pro, either in normal mode or safe mode to use the keyboard to log in DatBoys Data Recovery
I don't trust the sptd.sys driver. It is not essential (in my case, at least) to run alcohol 120%, although I've heard it is for daemon tools. It ruined my win7 boot and safe mode. Have used successfully several times, but not happy. Alexius
sptd.sys is a Daemon Tools and Alcohol 120%, I know sptd.sys may cause BSoD. It may harm all OS like MacOS, OS2 Warp, or WinXP and aynthing else :) a noob :X
Making XP Start Slow Or Crash LWReid
comes with Daemon Tools and it is not dangerous T
This is Daemon Tools drivers,and they can cause havy damage to your operation system(unable to boot it/safemode too).My recomendatons are:do not use daemon tools or alchohol 120% OR if you use them make BACKUP on your active partition with your operation system(use acronic true image home program) sptd.sys SUXS
Stopped my computer from booting Me
Daemon Tools. its 100% OK SKDA
Used in CD virtualization software such as Daemon Tools/Alcohol 120%. Causing BSOD on Windows 7 Systems. I would use the DuplexSecure SPTD uninstaller to delete sptd.sys Andrew
Active@ ISO Burner - version loaded with recent install seems to have given me TDSS rootkit. PITA
Used by CD virtualisation software such as Daemon Tools, Alcohol 120%. It must be removed in Windows 7 because they cause BSOD. Geek
Vital for CD/DVD emulation (Deamon tools, alcohol 120%. etc.) Use ERD commander to disable driver at stratup. Jonas
Its not dangerous to your system, but after install my maximum burn speed was a lot slower, burning +DL fast at 16x, now with this i cant burn the SAME EXACT MEDIA above 8x. Burning software also tells me to my face, that its the reason, causes all kindsa slow downs, crashes, etc.
XP w/ SP3 here. sptd.sys is in my C:\WINDOWS\system32\drivers folder. its size is 717.296 bluevic88
After deleting this .sys file,it is regenerated again.I don't know why... Manoj
Seems to be used in Alcohol120 and Daemon Tools, not vital but can come up with as a virus when running a scan  See also: Link NutC4ses
It can cause instability on your pc and some antivirus programs may identify it as a root kit but it isnt really dangerous PC man
Could it also come with VMWare's Player or Workstation? I have neither Daemon Tools nor Alcohol 120% installed but do have VMware Workstation installed. QBall
it is emulation software (it can stay on the system because of a uninstaller). It is not dangerous and causes not any problems on my system
TDSSkiller found this.Rootkit may be named it as SPTD Jith
I also loaded Active @ ISO Burner and a screen popped up saying SPTD was not found and to download it ...I have Deamon already and did not install from this prompt and Active ran fine so I bet that prompt was the virus version .... so Don't let Active install SPTD both my deamon shadow drives are working fine and I bet I have SPTD working when that after Active pop up said I didn't the pop up says SPTD not found and has install option remove option and another button I would not use it .....also this is a separate pop up after the Active wizard has finished it's set up fezz
SCSI Pass through driver, normally used for optical drive emulation. Loads very early during boot, so any problems are likely to give stop errors.
It was the cause of an IRQL_NOT_LESS_OR_EQUAL BSOD for me on Windows XP. I transfered it to another folder, so I temporarly remove it from where it was, and I succesfully booted Windows. Vibes
Daemon Tools Randum59
It`s used by CD/DVD virtualization programs such as Deamon Tools, Alcohol 120% etc. tinch
First I heard about sptd.sys was to 'press enter to contine loading SPTD.SYS' while trying to run in safe mode after nemurous errors(BSOD) kernal stack inpage errors and unmountable boot drive errors or something. My laptop is totalled :( Jonno
daemon tools!! Not harmful joker83
Daemon Tools Lite uses this for emulating disks. I have used it for years without a problem. BradH
Daemon Tools SCSI Pass Through Driver person
sptd.sys is used by Daemon Tools Tools version 4.00 . It is safe when u installed Deamon tools or else iyou will need to take a look on it. Sai
installed with Alcohol 120%, works fine Peter tH
i dont have alcohol or daemon tools but for some reason i do have sptd.sys and it caused massive booting problems and unmountable boot volume BSOD. supposedly duplexsecure has a removal tool but i dont trust using companies that make malware to successfully remove it. kaspersky's tdsskiller identifies this as a rootkit and will delete it on your behalf.  See also: Link filter
it's drver of Alcohol120%. not dangerous zuich
Used by both Alcohol 120% and Daemon Tools. Can cause some computers to experience boot issues and blue screens. Generally not dangerous except for those systems. Joseph
/%systemroot%/system32/drivers/sptd.sys Yes, it came with daemon tools (virtual device driver component), BUT seems to be acting like a ROOTKIT. Also it automatically loads two other suspicious kernel mode drivers: "sp+some characters.sys" and "random character name.sys" (thouse "random chars" in their names were different every time i boot-up my pc). None of this two drivers actually existed as file on the hard disk. They`ve been only loaded in operating memory, and unloaded on restart (after which loaded again under differ random names). These drivers with SPDT.sys itsef been detected by antivirus to intercept some nt_sys calls and os kernel communication (rootkit kind of shit!), messing with TCP network functionality and significantly slowing down system performance (on my pc at least). Daemon tools leave this driver even after full uninstallation (i wonder why? :) ). I managed to get rid of it without loosing current windows installation and... i gotta tell you - that was a challenge. Randomly-named drivers disappeared right after sptd.sys was removed permanently. _zero
Spdt shows up in a Root Kit Revealer as a zero length key and denies access to the Cfg registry key. This what caused me concern. I'm sure that it was installed with Alcohol 120%. So far I don't believe that it has caused me any problems. There is alot of conflicting discussion about this process. Dragonlx
Not harmful. It keeps rebooting my system and freezing in safe mode. Marshall
Daemon Tools - Scsi Pass Through Direct (sptd.sys) driver
after deinstalling Damon Tools the file persists. Avira can't open it. J_Dude3
It is a safe file however in some cases it can cause problems and give BSOD, easiest fix as it is NOT an essential driver is to search for the file and just delete it, this eill solve the BSOD problems Stefan
AVG warns as rootkit so to disable: http://www.duplexsecure.com/en/faq  See also: Link Laurence Smith
RootkitRevealer detects sptd.sys when run; AVG 2014 detects other variants of it as a rootkit. It hasn't caused me a problem on XP, I have DAEMON tools lite installed. So, this is where the pest came from. I'm not sure what to do with it at the moment, as a registry mis-edit could crash my computer upon re-boot or make the computer totally unusable. Brandon
Starburn free burning install it too. This is a tool for burning.  See also: Link Colpix
Driver used by the CD Rom emulation program, Daemon Tools  See also: Link victor
if installed with win 8.1 causes problems booting ..Recomand not install !!!!! Cristian Nitulescu
Caused BSOD 7E when system installed on new hardware. Had to disable the driver via Safe Mode Autoruns to fix. As noted elsewhere, is one of the first drivers to load and will prevent NTBOOTLOG from being generated. Alan

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Is sptd.sys spyware or a virus, trojans, adware or worm? Is there a known sptd.sys error?

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