It seems that the latest security patches from Microsoft, deployed over the last Patch Tuesday (22nd March), are causing serious problems for some users of Windows, including Windows 7.
In a nutshell, the affected Windows machines simply stop working and start displaying a (mostly) black screen, in some cases showing only a “My Computer” Explorer window.
The problem was first noticed by UK security company Prevx, which already offers a software fix. The folks at Prevx claim this is no small matter and that this “massively debilitating” issue could potentially affect “millions of Windows users.” However, no official fix is available from Microsoft yet.
A Microsoft representative said, “Microsoft is investigating reports that its latest release of security updates is resulting in system issues for some customers. Once we complete our investigation, we will provide detailed guidance on how to prevent or address these issues.”
If you have these symptoms you can safely try the free Black Screen Fix Available for users only. It will fix the most common cause we have seen of this issue. Running the fix program is easy under normal circumstances, simply download with your browser using the link above and run the program. However, if you are trying to do this from the PC which has the black screen it is a bit more tricky. In these circumstances follow the procedure below
Restart your PC
Logon and wait for the black screen to appear
Make sure your PC should be able to connect to the internet (black screen does not appear to affect this)
Press the Ctrl+Alt+Del keys simultaneously
When prompted, Click Start Task Manager
In Task Manager Click on the Application Tab
Next Click New Task
Now enter the command
Available for users only
Note this command assumes that you are using internet explorer as your browser, if not substitute your browser path and file details for those of iexplore.exe or use the Browser option of Task manager to locate it.
Click OK and your browser should start up and begin the download process
When prompted for the download Click run, the black screen fix program will download and run to automatically fix the issue.
Now restart your PC and the black screen problem will hopefully be gone.
Patch Detail
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The conditions under which the actual black screen is triggered are spasmodic. Some test systems always trigger the condition, others are less consistent. The windows patches which seem common to the issue arising are listed below:
KB915597 and KB976098
When the issue occurs the WinLogon Shell entry for Explorer.Exe becomes invalidated. The entry exists perfectly in the registry but is unusable/inaccessible and is therefore ignored by the OS resulting in the desktop and task bar not being loaded. This entry is frequently the target of malware so tightening access to it is probably a good thing. However, the black screen condition is the only sign of the problem, leaving non technical users with a major challenge.
