I am having an issue upgrading one particular plugin on a site of mine. All other plugins on this site upgrade without an issue. It is not a permissions issue as this has been checked multiple times and like I say all other plugins update perfectly.
The error occurs during the unzipping of the upgrade package. Specifically it occurs in the
The error is sometimes mkdir_failed_ziparchive (Could not create directory) and other times it is copy_failed_ziparchive (Could not copy file). The directory or file on which it fails varies.
It is not the first directory it tries to create or the first file it tries to copy. I have run the process with some logging code added and can see that it is able to create many directories/copy many files to the location in the wp-content/upgrade folder before throwing the error.
I am stumped as to what the cause could be and would appreciate any insights.