Last week when I installed CCleaner on my system, it also installed Avast antivirus software stealthily, in the background. After I uninstalled Avast, a registry key named AVAST Software still remained in the registry, but it couldn’t be opened. When the AVAST Software branch was selected, it threw the following error:
AVAST Software cannot be opened.
An error is preventing this key from being opened.
Details: The system cannot find the file specified.
When I opened the Properties of the AVAST Software key, the Security tab was blank, showing the message: The requested security information is either unavailable or can’t be displayed.
I tried running Sysinternals RegDelNull and Malwarebytes RegAssassin to nuke the keys, and they didn’t help.
Registry Reparse Point
Later I realized that the
HKEY_LOCAL_MACHINE\Software\AVAST Software is a reparse point or registry link that links to the following key on Windows 64-bit systems:
But, since the Avast uninstaller had wiped out the above key, the reparse point still remains but is orphaned.
On Windows 32-bit systems, the reparse point and the target key paths are reversed.
However, once I knew it’s only a reparse point, the fix turned out to be very simple; you don’t need to tinker with the registry key permissions.
Fix: Can’t delete Avast Software Registry Key
Method 1: Create AVAST Software key under WOW6432Node manually
To successfully remove the
AVAST Software reparse point, first, manually create the missing target key. Follow these steps:
- Start the Registry Editor (
- Create the
AVAST Softwarekey under the
Alternately, run the following command from an admin Command Prompt window to create the key manually on a Windows 64-bit system:
reg add "HKLM\Software\AVAST Software" /reg:32
- Then, go to the following key in the Registry Editor and delete it:
This deletes the linked key as well as the reparse point in one go.
Important Note: If, the
WOW6432Node\AVAST Software key is the reparse point itself (32bit vs 64-bit Windows) which can’t be opened, and points to the key
Software\AVAST Software, then you’ll need to create the target key (
HKLM\Software\AVAST Software) key manually before deleting the reparse point.
Method 2: Use AvRegLink.exe from Avast Software
Avast software has a tool named
AvRegLink.exe which can create, query or delete reparse points in the registry. This tool can be downloaded from the following URL:
Once downloaded, open admin Command Prompt and run the following command:
AvRegLink.exe delete "SOFTWARE\AVAST Software"
WOW6432Node\AVAST Software key is the reparse point itself (32bit vs 64-bit Windows), which points to the key
Software\AVAST Software, then you’ll need to run this command instead:
AvRegLink.exe delete "SOFTWARE\WOW6432Node\AVAST Software"
Before deleting the reparse point, if you want to query the reparse point to know where it’s pointing to, use this command-line:
AvRegLink.exe query "SOFTWARE\AVAST Software" AvRegLink.exe query "SOFTWARE\WOW6432Node\AVAST Software"
To create a reparse point manually, use this command-line syntax:
AvRegLink.exe create LinkKey TargetKey
You may also use regln: Windows Registry Linking Utility to create or delete reparse points in the registry.
That’s it! This deletes the AVAST Software registry key from the
HKEY_LOCAL_MACHINE\Software or the
HKEY_LOCAL_MACHINE\WOW6432Node\Software registry locations.
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About the author
Ramesh Srinivasan founded Winhelponline.com back in 2005. He is passionate about Microsoft technologies and he has been a Microsoft Most Valuable Professional (MVP) for 10 consecutive years from 2003 to 2012.