Since applying NW 6.5 SP6 we've been unable to upload to Netstorage.

I get the popup window, I can browse to and select the file, then I click on the UPLOAD button. It appears to start the upload, but then fails and the upload window changes to "Error uploading some or all of the files".
In looking at the target directory, there is a deleted file with the same name that is 0 bytes in size. (that's why I think it starts to upload)

I've looked at TID 3592807 and 10070833, but neither of them have fixed the issue.

Help, please?