I'm in the same boat as many others with x64 Windows 8.1 Pro.   I have a microsoft account that works fine on all my machines except my main desktop. It stopped syncing skydrive on 10/22 (which is when I think I upgraded or shortly thereafter).     There is no sync in either direction.   My win8 configuration had the desktop skydrive installed (and the program files appears to be there because there is a skydrive setup .exe for the desktop app, by how things look on the command prompt).

Anyhow, I don't see a skydrive background process in task manager and nothing happens if I try to run skydrive.exe by command prompt.   The files in there are 'available offline' but nothing syncs.   In file explorer, the skydrive icon shows the sync symbol.   The modern app shows no information in the upper right at all (I just get the moving dots across the top of the screen..forever).

I'll have to make a decision soon because I do all my work on this thing; either doing a system restore, complete wipe or hoping microsoft puts out a patch or something.

If anyone has advice, I'm all ears.