Jump to content

Recommended Posts

  • Staff

What is System Diagnostics?

The Malwarebytes research team has determined that System Diagnostics is a "system optimizer". These so-called "system optimizers" use intentional false positives to convince users that their systems have problems. Then they try to sell you their software, claiming it will remove these problems.
More information can be found on our Malwarebytes Labs blog.

How do I know if I am infected with System Diagnostics?

This is how the main screen of the system optimizer looks:


You will find these icons in your taskbar, your startmenu, and on your desktop:


and see this warning during install:


and these screens during "operations":



You may see this entry in your list of installed programs:


How did System Diagnostics get on my computer?

These so-called system optimizers use different methods of getting installed. This particular one was pushed by fake online scanners.

How do I remove System Diagnostics?

Our program Malwarebytes can detect and remove this potentially unwanted application.

  • Please download Malwarebytes to your desktop.
  • Double-click mb3-setup-consumer-{version}.exe and follow the prompts to install the program.
  • Then click Finish.
  • Once the program has fully updated, select Scan Now on the Dashboard. Or select the Threat Scan from the Scan menu.
  • If another update of the definitions is available, it will be implemented before the rest of the scanning procedure.
  • When the scan is complete, make sure that all Threats are selected, and click Remove Selected.
  • Restart your computer when prompted to do so.

Is there anything else I need to do to get rid of System Diagnostics?

  • No, Malwarebytes removes System Diagnostics completely.
  • The shortcut called System Diagnostics on the desktop can be deleted if it belonged to the system optimizer.

How would the full version of Malwarebytes help protect me?

We hope our application and this guide have helped you eradicate this system optimizer.

As you can see below the full version of Malwarebytes would have protected you against the System Diagnostics installer. It would have warned you before the application could install itself, giving you a chance to stop it before it became too late.



and we block access to their domain:


Technical details for experts

You may see these entries in FRST logs:


(SystemDiagnostics.com) C:\Program Files (x86)\System Diagnostics\PCDUI.exe
C:\Users\Public\Desktop\System Diagnostics.lnk
C:\ProgramData\Microsoft\Windows\Start Menu\Programs\System Diagnostics
C:\Program Files (x86)\System Diagnostics

System Diagnostics (HKLM-x32\...\75C0CFDE-332C-4C62-9264-418F03AE2CD8_is1) (Version: - pccheckuppro.com)

Alterations made by the installer:

File system details [View: All details] (Selection)
    Adds the folder C:\Program Files (x86)\System Diagnostics
       Adds the file AMPIEDecoder.dll"="1/28/2016 4:33 PM, 166912 bytes, A
       Adds the file HtmlRenderer.dll"="5/6/2015 10:38 AM, 221696 bytes, A
       Adds the file HtmlRenderer.WinForms.dll"="5/6/2015 10:38 AM, 60416 bytes, A
       Adds the file Interop.IWshRuntimeLibrary.dll"="6/13/2017 8:55 PM, 55528 bytes, A
       Adds the file Interop.WUApiLib.dll"="2/12/2016 2:18 PM, 86016 bytes, A
       Adds the file Microsoft.TeamFoundation.Common.dll"="3/14/2013 11:05 PM, 680064 bytes, A
       Adds the file NAudio.dll"="3/5/2015 6:56 PM, 471040 bytes, A
       Adds the file Newtonsoft.Json.dll"="9/18/2015 6:21 PM, 465408 bytes, A
       Adds the file PCDEngine.dll"="6/13/2017 8:49 PM, 674304 bytes, A
       Adds the file PCDRes.dll"="6/6/2017 12:46 PM, 1848320 bytes, A
       Adds the file PCDUI.exe"="6/13/2017 8:55 PM, 1219816 bytes, A
       Adds the file PCDUI.exe.config"="6/6/2017 1:28 PM, 3398 bytes, A
       Adds the file System.Data.SQLite.DLL"="5/7/2015 4:37 PM, 290816 bytes, A
       Adds the file System.Data.SQLite.Linq.dll"="5/7/2015 4:37 PM, 196608 bytes, A
       Adds the file System.Threading.dll"="1/22/2016 9:15 PM, 387408 bytes, A
       Adds the file TAFactory.IconPack.dll"="7/17/2012 9:33 PM, 36864 bytes, A
       Adds the file unins000.dat"="5/11/2018 8:15 AM, 77053 bytes, A
       Adds the file unins000.exe"="5/11/2018 8:15 AM, 1264360 bytes, A
       Adds the file unins000.msg"="5/11/2018 8:15 AM, 22701 bytes, A
    Adds the folder C:\Program Files (x86)\System Diagnostics\langs
       Adds the file english_apc_en.ini"="5/15/2017 5:24 PM, 66374 bytes, A
    Adds the folder C:\Program Files (x86)\System Diagnostics\x64
       Adds the file SQLite.Interop.dll"="5/7/2015 4:37 PM, 1175552 bytes, A
    Adds the folder C:\Program Files (x86)\System Diagnostics\x86
       Adds the file SQLite.Interop.dll"="5/7/2015 4:37 PM, 854528 bytes, A
    Adds the folder C:\ProgramData\Microsoft\Windows\Start Menu\Programs\System Diagnostics
       Adds the file Buy System Diagnostics.lnk"="5/11/2018 8:15 AM, 1088 bytes, A
       Adds the file System Diagnostics.lnk"="5/11/2018 8:15 AM, 1076 bytes, A
    Adds the folder C:\Users\{username}\AppData\Roaming\SystemDiagnostics.com\System Diagnostics
       Adds the file Errorlog.txt"="5/11/2018 8:16 AM, 418 bytes, A
    Adds the folder C:\Users\{username}\AppData\Roaming\SystemDiagnostics.com\System Diagnostics\smico
    In the existing folder C:\Users\Public\Desktop
       Adds the file System Diagnostics.lnk"="5/11/2018 8:15 AM, 1058 bytes, A

Registry details [View: All details] (Selection)
       "DisplayIcon"="REG_SZ", "C:\Program Files (x86)\System Diagnostics\PCDUI.exe"
       "DisplayName"="REG_SZ", "System Diagnostics"
       "DisplayVersion"="REG_SZ", ""
       "EstimatedSize"="REG_DWORD", 9985
       "Inno Setup: App Path"="REG_SZ", "C:\Program Files (x86)\System Diagnostics"
       "Inno Setup: Icon Group"="REG_SZ", "System Diagnostics"
       "Inno Setup: Language"="REG_SZ", "en"
       "Inno Setup: Setup Version"="REG_SZ", "5.5.9 (u)"
       "Inno Setup: User"="REG_SZ", "{username}"
       "InstallDate"="REG_SZ", "20180511"
       "InstallLocation"="REG_SZ", "C:\Program Files (x86)\System Diagnostics\"
       "MajorVersion"="REG_DWORD", 1
       "MinorVersion"="REG_DWORD", 0
       "NoModify"="REG_DWORD", 1
       "NoRepair"="REG_DWORD", 1
       "Publisher"="REG_SZ", "pccheckuppro.com"
       "QuietUninstallString"="REG_SZ", ""C:\Program Files (x86)\System Diagnostics\unins000.exe" /SILENT"
       "UninstallString"="REG_SZ", ""C:\Program Files (x86)\System Diagnostics\unins000.exe""
       "VersionMajor"="REG_DWORD", 1
       "VersionMinor"="REG_DWORD", 0
       "affiliateid"="REG_SZ", ""
       "country"="REG_SZ", ""
       "efophone"="REG_SZ", "(855)-392-7237"
       "LangCode"="REG_SZ", "en"
       "phone"="REG_SZ", "(877)-883-7061"
       "pxl"="REG_SZ", ""
       "showefono"="REG_DWORD", 1
       "utm_campaign"="REG_SZ", "sysd"
       "utm_medium"="REG_SZ", "sysd"
       "utm_pubid"="REG_SZ", ""
       "utm_source"="REG_SZ", "sysd"
       "x-at"="REG_SZ", ""
       "x-context"="REG_SZ", ""
    [HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\SystemDiagnostics.com\System Diagnostics]
       "affiliateid"="REG_SZ", ""
       "affired"="REG_DWORD", 1
       "afterInstallUrl"="REG_SZ", "http://www.pccheckuppro.com/apc/afterinstall/?"
       "cbkpoff"="REG_DWORD", 1
       "country"="REG_SZ", ""
       "cta"="REG_DWORD", 0
       "delay"="REG_DWORD", 0
       "EmailURL"="REG_SZ", "support@pccheckuppro.com"
       "expired"="REG_DWORD", 0
       "Installstring"="REG_SZ", "C:\Program Files (x86)\System Diagnostics"
       "isphone"="REG_DWORD", 1
       "issilent"="REG_DWORD", 0
       "LangCode"="REG_SZ", "en"
       "lcname"="REG_SZ", "Tech Live Connect"
       "msl"="REG_DWORD", 1
       "ovoffdis"="REG_DWORD", 0
       "phone"="REG_SZ", "(877)-883-7061"
       "Phone_at"="REG_SZ", "(800)-180-0926"
       "Phone_au"="REG_SZ", "1800-764-389"
       "Phone_ch"="REG_SZ", "(800)-180-0926"
       "Phone_de"="REG_SZ", "(800)-180-0926"
       "Phone_fr"="REG_SZ", "(334)-88627945"
       "Phone_gb"="REG_SZ", "(800)-404-8430"
       "Phone_lu"="REG_SZ", "(800)-180-0926"
       "Phone_uk"="REG_SZ", "(800)-404-8430"
       "Phone_us"="REG_SZ", "(877)-883-7061"
       "playsound"="REG_DWORD", 1
       "prereg"="REG_DWORD", 0
       "PurchaseURL"="REG_SZ", "http://www.pccheckuppro.com/sysd/price.asp?"
       "pxl"="REG_SZ", ""
       "reg"="REG_DWORD", 0
       "RenewURL"="REG_SZ", "http://www.pccheckuppro.com/sysd/renewal.asp?"
       "showtn"="REG_DWORD", 0
       "supporturl"="REG_SZ", "http://www.pccheckuppro.com/help/"
       "utm_campaign"="REG_SZ", "sysd"
       "utm_medium"="REG_SZ", "sysd"
       "utm_source"="REG_SZ", "sysd"
       "WebURL"="REG_SZ", "http://www.pccheckuppro.com/"
       "x-at"="REG_SZ", ""
       "x-context"="REG_SZ", ""
       "data"="REG_BINARY, .....................................................................................................................................................................................................................................................................................................................................
    [HKEY_CURRENT_USER\Software\SystemDiagnostics.com\System Diagnostics]
       "affiliateid"="REG_SZ", ""
       "Installstring"="REG_SZ", "C:\Program Files (x86)\System Diagnostics"
       "LangCode"="REG_SZ", "en"
       "pxl"="REG_SZ", ""
       "utm_campaign"="REG_SZ", "sysd"
       "utm_medium"="REG_SZ", "sysd"
       "utm_pubid"="REG_SZ", ""
       "utm_source"="REG_SZ", "sysd"
       "x-at"="REG_SZ", ""
       "x-context"="REG_SZ", ""
    [HKEY_CURRENT_USER\Software\SystemDiagnostics.com\System Diagnostics\]

Malwarebytes log:


-Log Details-
Scan Date: 5/11/18
Scan Time: 8:19 AM
Log File: 498020c7-54e3-11e8-a1d9-080027235d76.json
Administrator: Yes

-Software Information-
Components Version: 1.0.262
Update Package Version: 1.0.5066
License: Premium

-System Information-
OS: Windows 7 Service Pack 1
CPU: x64
File System: NTFS
User: {computername}\{username}

-Scan Summary-
Scan Type: Threat Scan
Result: Completed
Objects Scanned: 239265
Threats Detected: 37
Threats Quarantined: 37
Time Elapsed: 2 min, 35 sec

-Scan Options-
Memory: Enabled
Startup: Enabled
Filesystem: Enabled
Archives: Enabled
Rootkits: Enabled
Heuristics: Enabled
PUP: Detect
PUM: Detect

-Scan Details-
Process: 0
(No malicious items detected)

Module: 0
(No malicious items detected)

Registry Key: 4
PUP.Optional.PCVARK, HKLM\SOFTWARE\WOW6432NODE\MICROSOFT\WINDOWS\CURRENTVERSION\UNINSTALL\75C0CFDE-332C-4C62-9264-418F03AE2CD8_is1, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, HKCU\SOFTWARE\SystemDiagnostics.com, Quarantined, [401], [520053],1.0.5066
PUP.Optional.PCVARK, HKLM\SOFTWARE\WOW6432NODE\SystemDiagnostics.com, Quarantined, [401], [520052],1.0.5066
PUP.Optional.WinYahoo, HKLM\SOFTWARE\WOW6432NODE\PCV-VARS, Quarantined, [246], [254813],1.0.5066

Registry Value: 1
PUP.Optional.WinYahoo, HKLM\SOFTWARE\WOW6432NODE\PCV-VARS|AFFILIATEID, Quarantined, [246], [254813],1.0.5066

Registry Data: 0
(No malicious items detected)

Data Stream: 0
(No malicious items detected)

Folder: 7
PUP.Optional.PCVARK, C:\Program Files (x86)\System Diagnostics\langs, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\Program Files (x86)\System Diagnostics\x64, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\Program Files (x86)\System Diagnostics\x86, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\PROGRAM FILES (X86)\SYSTEM DIAGNOSTICS, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\Users\{username}\AppData\Roaming\SystemDiagnostics.com\System Diagnostics\smico, Quarantined, [401], [520045],1.0.5066
PUP.Optional.PCVARK, C:\Users\{username}\AppData\Roaming\SystemDiagnostics.com\System Diagnostics, Quarantined, [401], [520045],1.0.5066
PUP.Optional.PCVARK, C:\USERS\{username}\APPDATA\ROAMING\SYSTEMDIAGNOSTICS.COM, Quarantined, [401], [520045],1.0.5066

File: 25
PUP.Optional.PCVARK, C:\PROGRAM FILES (X86)\SYSTEM DIAGNOSTICS\UNINS000.DAT, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\Program Files (x86)\System Diagnostics\langs\english_apc_en.ini, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\Program Files (x86)\System Diagnostics\x64\SQLite.Interop.dll, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\Program Files (x86)\System Diagnostics\x86\SQLite.Interop.dll, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\Program Files (x86)\System Diagnostics\PCDEngine.dll, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\Program Files (x86)\System Diagnostics\AMPIEDecoder.dll, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\Program Files (x86)\System Diagnostics\HtmlRenderer.dll, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\Program Files (x86)\System Diagnostics\HtmlRenderer.WinForms.dll, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\Program Files (x86)\System Diagnostics\Interop.IWshRuntimeLibrary.dll, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\Program Files (x86)\System Diagnostics\Interop.WUApiLib.dll, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\Program Files (x86)\System Diagnostics\Microsoft.TeamFoundation.Common.dll, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\Program Files (x86)\System Diagnostics\NAudio.dll, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\Program Files (x86)\System Diagnostics\Newtonsoft.Json.dll, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\Program Files (x86)\System Diagnostics\PCDRes.dll, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\Program Files (x86)\System Diagnostics\PCDUI.exe, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\Program Files (x86)\System Diagnostics\PCDUI.exe.config, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\Program Files (x86)\System Diagnostics\System.Data.SQLite.DLL, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\Program Files (x86)\System Diagnostics\System.Data.SQLite.Linq.dll, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\Program Files (x86)\System Diagnostics\System.Threading.dll, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\Program Files (x86)\System Diagnostics\TAFactory.IconPack.dll, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\Program Files (x86)\System Diagnostics\unins000.exe, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\Program Files (x86)\System Diagnostics\unins000.msg, Quarantined, [401], [520044],1.0.5066
PUP.Optional.PCVARK, C:\Users\{username}\AppData\Roaming\SystemDiagnostics.com\System Diagnostics\Errorlog.txt, Quarantined, [401], [520045],1.0.5066
PUP.Optional.PCVARK, C:\USERS\{username}\DESKTOP\SYSDSETUPSITE.EXE, Quarantined, [401], [516157],1.0.5066
PUP.Optional.PCVARK, C:\USERS\{username}\DOWNLOADS\UNCONFIRMED 397119.CRDOWNLOAD, Quarantined, [401], [516157],1.0.5066

Physical Sector: 0
(No malicious items detected)


As mentioned before the full version of Malwarebytes could have protected your computer against this threat.
We use different ways of protecting your computer(s):

  • Dynamically Blocks Malware Sites & Servers
  • Malware Execution Prevention

Save yourself the hassle and get protected.

Link to post
Share on other sites

  • Recently Browsing   0 members

    • No registered users viewing this page.
Back to top
  • Create New...

Important Information

This site uses cookies - We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.