This just started in the past day or so, and perhaps is related to an update to DJO in my phone. It was at DJO 4.4.2, build 1038, and is now at 4.4.3, build 1062.
Doing a USB sync, on the phone when it appears to be done (based on the message on the computer in Companion Link), the phone message stays on "Press OK when the PC sync is complete" with the arrow spinning. Last night I finally tapped OK, and then got a message saying that it couldn't find the DJO database. Among the options was to restore a database dated that day. Took a deep breath and did that, and all was fine - recent changes on each side were indeed synced and the same.
Right now I'm sitting here watching it spin, and don't think it will stop. How can I deal with this without risking losing my data? Is it something in the new update to DJO?

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Samsung Galaxy S5, Android 6.0.1 (security patch level August 1, 2017)
DJO 4.4.3, build 1062; CL 7050
Win10 x64, Fall Creator/April 2018 update, v 1803; PalmDesktop 4.2

Local WiFi sync --- manual syncing, as needed
Not syncing to native Android calendar or contacts