Updating help for the PSReadLine module
You may have noticed an error message when trying to update the help for the PSReadLine module.
In the example above, I am trying to update help for the PSReadLine module on my Windows
computer. Take a close look at the error message. Notice the spelling of the module name in the
Failed to update Help for the module(s) ‘PSReadline‘
In PowerShell 6 and higher, the PSReadLine module is spelled with a capital
L character. But the
error message is using a lowercase letter.
The root cause of the error
The problem comes from Windows PowerShell 5.1. The version of the PSReadline module that shipped
in Windows PowerShell 5.1 used a lowercase letter in the name. The name of the module was changed
for the release of PowerShell 6. It now uses a capital
L in the name.
Update-Help cmdlet constructs the URL of the CAB file containing the updated help. The URL
path is case-sensitive. The updated help files use the new name with the capital
L. PowerShell 6
and higher is installed side-by-side with Windows PowerShell. When you run
Update-Help, the cmdlet
attempts to update the help for both versions of PowerShell. The name of the module that
Update-Help uses is based on the name of the folder where the help is stored. For Windows
PowerShell this is
Note that only the update of help for the Windows PowerShell location is failing.
How to fix this problem
Fortunately the fix is simple. Just rename the folder to
C:Program FilesWindowsPowerShellModulesPSReadLine. To rename this folder, you must be sure to
close all Windows PowerShell sessions to release any open file handles on the directory. Use the
Windows File Explorer to rename the file. If you try to rename the folder from the command line, you
receive the following error message.
Rename-Item: Source and destination path must be different.