I had this the other day, then a 680 soft reset and a Mac OS update seemed to sort it. Now it's happening again: if I go to send memo by bluetooth to my Mac it fails with the error message:
An error occurred while saving the file
The file being sent to you could not be saved on your disk. Perhaps the receive folder is located on locked volume. Try changing the destination volume and trying again.

Bluetooth sending still works for othe apps, so it seems t be a Memos exclusive bogey.

The commanality/ trigger event seems to be that I've used the Memo/ Memopad conduit in Missing Sync, firt time because I didn't realize M/S Memopad has its own identically designated (Memopad) conduit, today as I was doing a final dump of the data of my (soon to be ex) TX.

Any clues anyone? I've tried soft resetting, and restarting the Mac. I can't do more updating (on latest iteration already)