could you tell me exactly?

i guess, this problem can be due to using multiple users of this software on a local server as simultaneously.

in result, your directory changed to another users's directory.

in to fix this error, you should correct your document directory:

open the gaussian >> select "file" >> select "preference" >> repair outpit path to your document path >> "ok"

good luck

This error message also appears if the previous compute job did not finish normally but was terminated abruptly. In that case, the file gxx.inp has to be manually removed/deleted from the Gaussian folder that is called "scratch" (it is generally recommended to not just delete a file but to keep a copy at a different location - just in case).