I have spent the last 3 hours trying to get Lightroom mobil to work so I can share images with a client. If I go and look at the link provided on adobe.ly for publicly sharing the photos it comes up with a screen showing that there should be a number of images there, but every single one is shown a a place holder icon of a cloud with an exclamation mark in it, which if you click on any of them states 'image unavailable'. If I look in my Lightroom mobile tab of the Preferences dialogue it states that all the photos are synced.
Having searched for solutions to similar problems to this I have tried the following:
Re-installed Lightroom and CC - No difference in behaviour,
Selected 'Delete all Data' from the Lightroom mobile tab - this did delete everything but didn't resolve the issue,
I have re-installed Lightroom and removed the whole of 'C:\Users\<user>\AppData\Local\Adobe\Lightroom\Caches' between installs thinking that the removal of 'Sync.lrdata' might fix it - No difference in behaviour.
At this point I am stumped! Is there any way to find out what is causing it to hang and get it going again!
Would you please try to sync images from a new catalog and check if that helps.
If you still see the problem can you also try flushing the dns cache on Windows?
1. Shut down Lightroom
2. Open a windows command prompt (Start -> Run -> cmd.exe)
3. Type 'ipconfig /flushdns' and hit enter (no quotes)
4. Restart machine
5. Start Lightroom, attempt to sync a new image and see if it gets posted properly
If the issue still persist please share the diagnostic logs with us so that we can provide a better resolution.
You can trigger the log via LR Desktop preferences -> Lightroom Mobile and when you hold down the alt key you will notice a generate diagnostic log button.