I haven't had the error message yet, but could it be that the USB stick (or whatever) is corrupted?

Thanks, but I don't think so, as I'm able to export other projects to the same stick - and this one sometimes. 

Anne. can you try export locally and then copy to USB?

Is this USB device used for anything else (eg synchonised backup)?

Hi Anne, 

I would suggest you to export the project locally first and subsequently save it on USB, like Esahc suggested. 

Thanks! Kind regards.

Thanks for the suggestions.

Yes, I can export the project locally and move it to the memory stick - but I've also exported it directly to the same stick this morning without any problem. Sometimes it works, sometimes I get the error message. Very weird. 

The memory stick isn't used for anything else, it's just a backup with exports of all my projects on it, and there's loads of spare capacity. 

Hi Anne!

Were you able to complete the export now?

Thanks! Kind regards.

I've been able to export with no problem for the three days . . . but today I get the same error message. 

Just tried a second time and it's worked fine. 

It is advisable to get a second USB stick and save the files there as well, better save twice.

The USB flash drive's internal software changes the storage locations to achieve even wear of the material, but eventually the material will wear out and the USB flash drive will no longer be able to store.

Daniel's suggestion seemed sensible, so for the last twelve days I've been exporting to a differeent stick with no problem - until today. Now, I'm getting the same error message when trying to export the same project as before. I don't get it with any other projects, only this one.