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Error Message on Auto Update of Firefox

Greetings, Team. When Firefox does an Auto-update while starting, an error message arrives, " NSIS Error:

Error writing temporary file. Make sure your temp folder is valid.

OK " Please, where and what name does this 'temp folder' have?

How may I fix this Error?

Thank y'all in advance. Phil T. ps W10, Chkdsk OK, system appears OK.

Greetings, Team. When Firefox does an Auto-update while starting, an error message arrives, " NSIS Error: Error writing temporary file. Make sure your temp folder is valid. OK " Please, where and what name does this 'temp folder' have? How may I fix this Error? Thank y'all in advance. Phil T. ps W10, Chkdsk OK, system appears OK.
Attached screenshots

All Replies (1)

With all apps closed, navigate to C:\Users\YourUsername\AppData\Local\Temp and erase everything in the folder. Then do the same in C:\Windows\Temp in File Explorer, then press Ctrl + A to select all, and delete. Skip any files that are reported as "in use".

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