Devices disappearing

Has anyone else had the issue where random devices just disappear during uploads?
This is what I get:
Error: Unable to transfer to Lower Sitting > At Hot Tub Door > Sconces. The device is not communicating.
Either the device is not powered on, out of range of any repeaters, or has been deactivated.
1. the device is not powered off
2. it is well in range of repeaters
3. it has not been deactivated.
As a matter of fact, it probably still works just fine. I would just feel a whole lot better seeing that every device has gotten it's database and is all good.

That's been known to happen. Wait until nearly the entire database pulls that on you on your "last" transfer before going home. Sometimes it's just a glitch, and is easily resolved by hitting "retry failed devices"- only transfers to those that did not get an update. Of note, if no changes were made that the dimmer/device in question is involved in, then just move on. If the transfer does involve changes to that specific device, the you may have to deactivate/reactivate.

Or, in persistently weird situations, delete the device AND the room containing it and recreate them both. In my case the database was somehow corrupted for just that ONE room and anything put into the configuration for it. Damnedest thing...

Devices can continue to work just fine because they don't depend on having a wireless connection to operate. It's only scenes or interaction with other keypads/programming that would fail.

I'd start by loading an older configuration (you DO store separate copies for each revision, right?) and see if that transfers properly. If so, then worry about your current database in the software.