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26 October 2017
Infection Length:
System Checkup
iolo technologies, LLC
Risk Impact:
Systems Affected:


PUA.SystemCheckup is a potentially unwanted application that gives misleading information about issues on the computer.

Antivirus Protection Dates

  • Initial Rapid Release version 25 October 2017 revision 004
  • Latest Rapid Release version 30 July 2018 revision 035
  • Initial Daily Certified version 25 October 2017 revision 018
  • Latest Daily Certified version 31 July 2018 revision 001
  • Initial Weekly Certified release date 01 November 2017
Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.
Once executed, the application creates the following folders:
  • %SystemDrive%\Documents and Settings\admin\Application Data\iolo
  • %SystemDrive%\Documents and Settings\All Users\Application Data\iolo
  • %SystemDrive%\Documents and Settings\All Users\Application Data\iolo\logs
  • %SystemDrive%\Documents and Settings\All Users\Application Data\iolo\SCU
  • %ProgramFiles%\iolo
  • %ProgramFiles%\iolo\System Checkup

The application creates the following files:
  • %AllUsersProfile%Application Data\iolo\logs\Setup Log 2017-9-1.txt
  • %AllUsersProfile%Application Data\iolo\SCU\fileinfo.dll
  • %AllUsersProfile%Application Data\iolo\SCU\scuebhtml.dll
  • %AllUsersProfile%Application Data\iolo\SCU\sculnch.lnk
  • %AllUsersProfile%Application Data\iolo\SCU\scuststr.lnk
  • %AllUsersProfile%Application Data\iolo\SCU\scutstr.dll
  • %AllUsersProfile%Application Data\iolo\SCU\smscn.dll
  • %AllUsersProfile%Documents\My Pictures\Sample Pictures\Thumbs.db
  • %ProgramFiles%\iolo\System Checkup\SysCheckup.exe
  • %ProgramFiles%\iolo\System Checkup\uninstsms.exe

Next, the application creates the following registry entries:
  • HKEY_LOCAL_MACHINE\SOFTWARE\iolo\Installed Products\{918D30D3-AD9B-43A8-9EF7-463075DC93CD}\"AppKey" = "\Software\iolo\System Checkup"
  • HKEY_LOCAL_MACHINE\SOFTWARE\iolo\Installed Products\{918D30D3-AD9B-43A8-9EF7-463075DC93CD}\"Version" = ""
  • HKEY_LOCAL_MACHINE\SOFTWARE\iolo\System Checkup\"AppPath" = "%ProgramFiles%\iolo\System Checkup\SysCheckup.exe"
  • HKEY_LOCAL_MACHINE\SOFTWARE\iolo\System Checkup\2Version" = ""
  • HKEY_LOCAL_MACHINE\SOFTWARE\iolo\System Checkup\"wugroupid" = "E7"
  • HKEY_LOCAL_MACHINE\SOFTWARE\iolo\System Checkup\"sitype" = "1"
  • HKEY_LOCAL_MACHINE\SOFTWARE\iolo\System Checkup\"sirpt" = "1"
  • HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{918D30D3-AD9B-43A8-9EF7-463075DC93CD}_is1\"Comments" = "Copyright 1998-2017 iolo technologies, LLC. All rights reserved"
  • HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{918D30D3-AD9B-43A8-9EF7-463075DC93CD}_is1\"Contact" = ""
  • HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{918D30D3-AD9B-43A8-9EF7-463075DC93CD}_is1\"DisplayIcon" = "%ProgramFiles%\iolo\System Checkup\SysCheckup.exe"
  • HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{918D30D3-AD9B-43A8-9EF7-463075DC93CD}_is1\"DisplayName" = "System Checkup 4.0"
  • HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{918D30D3-AD9B-43A8-9EF7-463075DC93CD}_is1\"DisplayVersion" = ""
  • HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{918D30D3-AD9B-43A8-9EF7-463075DC93CD}_is1\"InstallDate" = "20170901"
  • HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{918D30D3-AD9B-43A8-9EF7-463075DC93CD}_is1\"InstallLocation" = "%ProgramFiles%\iolo\System Checkup\"
  • HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{918D30D3-AD9B-43A8-9EF7-463075DC93CD}_is1\"MajorVersion" = "4"
  • HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{918D30D3-AD9B-43A8-9EF7-463075DC93CD}_is1\"MinorVersion" = "0"
  • HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{918D30D3-AD9B-43A8-9EF7-463075DC93CD}_is1\"NoModify" = "1"
  • HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{918D30D3-AD9B-43A8-9EF7-463075DC93CD}_is1\"NoRepair" = "1"
  • HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{918D30D3-AD9B-43A8-9EF7-463075DC93CD}_is1\"Publisher" = "iolo technologies, LLC"
  • HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{918D30D3-AD9B-43A8-9EF7-463075DC93CD}_is1\"QuietUninstallString" = "%ProgramFiles%\iolo\System Checkup\uninstsms.exe /uninstall"
  • HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{918D30D3-AD9B-43A8-9EF7-463075DC93CD}_is1\"UninstallString" = "%ProgramFiles%\iolo\System Checkup\uninstsms.exe /uninstall"
  • HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{918D30D3-AD9B-43A8-9EF7-463075DC93CD}_is1\"URLInfoAbout" = ""

The application performs a scan and displays misleading information about issues on the computer.

You may have arrived at this page either because you have been alerted by your Symantec product about this risk, or you are concerned that your computer has been affected by this risk.

Before proceeding further we recommend that you run a full system scan . If that does not resolve the problem you can try one of the options available below.

If you are a Norton product user, we recommend you try the following resources to remove this risk.

Removal Tool

If you have an infected Windows system file, you may need to replace it using the Windows installation CD .

How to reduce the risk of infection
The following resources provide further information and best practices to help reduce the risk of infection.

If you are a Symantec business product user, we recommend you try the following resources to remove this risk.

Identifying and submitting suspect files
Submitting suspicious files to Symantec allows us to ensure that our protection capabilities keep up with the ever-changing threat landscape. Submitted files are analyzed by Symantec Security Response and, where necessary, updated definitions are immediately distributed through LiveUpdate™ to all Symantec end points. This ensures that other computers nearby are protected from attack. The following resources may help in identifying suspicious files for submission to Symantec.

Removal Tool

If you have an infected Windows system file, you may need to replace it using the Windows installation CD .

How to reduce the risk of infection
The following resource provides further information and best practices to help reduce the risk of infection.
Protecting your business network

The following instructions pertain to all current Symantec antivirus products.

1. Performing a full system scan
How to run a full system scan using your Symantec product

2. Restoring settings in the registry
Many risks make modifications to the registry, which could impact the functionality or performance of the compromised computer. While many of these modifications can be restored through various Windows components, it may be necessary to edit the registry. See in the Technical Details of this writeup for information about which registry keys were created or modified. Delete registry subkeys and entries created by the risk and return all modified registry entries to their previous values.