PCLZIP_ERR_MISSING_FILE (-4)

In the e107 website building system, which I have now used a few times to create various websites, I keep getting an error when I set up a new one.

It is the same error, and I have always forgotten how to fix it.

This error occurs when I am setting up a new theme or plugin, and the reply comes back with:

An error has occurred, unable to un-archive the file PCLZIP extract error: ‘PCLZIP_ERR_MISSING_FILE (-4)’

and

Error: The filetype application/x-zip-compressed is not allowed and has been deleted. (1)

Well, the simple answer, as a reminder for myself, and anyone searching for this, is:

Rename the file: e107_admin/filetypes_.php to filetypes.php (remove the underline before the dot.)

Also check the filetypes that are permitted actually include the one you need.
The default filetypes are: zip, gz, jpg, png and gif.