Error exporting WAV

I am trying to export a 3-minute Audacity file as a WAV, which I have done hundreds of times successfully. Recently an “Edit Metadata” window comes up, with some fields blank and some pre-filled. When I hit “OK” I get an error message saying:

"Error while writing WAV (Microsoft) file (disk full?). Libsndfile says “, 0sA (other garbage characters here)”.

There is plenty of available disk space on the server where I work, so the disk is not full. On the Edit Metadata window, if I hit “Clear” and then “OK” it works. But it creates a WAV file that is 10 times the size of what I normally create (36,000K instead of 3,500K) which is not a workable solution. What am I doing wrong? Thanks for your help.

There are some invalid (garbage) characters in the metadata.
Click the “Clear” button in the Metadata Editor, then continue with the export.