Hello @alejandro_shuttera,
You may want to have a look at some of the posts where users report this error, such as: The file could not be uploaded or revised. error
You can also search here on the forum for the string “file could not be uploaded or revised” and may find additional posts. It would be helpful, however, to have PHP error log messages here as they can help identify the problem. So, if you are able to post messages from your error log - that would be ideal.
-Roger
PKP Team