When running the SMF Upgrade Utility im getting this error message
The cache directory could not be found.
Please make sure you have a directory called "cache" in your forum directory before continuing.
That directory is actually there tried uploading again a few times but get same message
Which versions are you upgrading from -> to?
Upgrading from 2.0 to 2.0.15
Have you tried installing patches in package manager one step at a time, instead of using upgrade package?
Are permissions set right on the cache directory. ??
Try disabling cache all together and emptying out the cache, see if that makes a difference ;).
Oh, and run repair_settings.php after you disable the cache and clean the directory, see if all paths and URLs are correct ;).