Just used this resolution for Windows 7 Pro x86 with version 3.0.0 of Ubuntu One client for Windows and worked great! Thanks!I meet the same error in Windows
finally I got it
1.shutdown the 3 process contain ubuntu
such as windows-ubuntu-sso-login.exe
2.AND then GOTO the Folder such as
C:\Documents and Settings\Administrator\Local Settings\Application Data\xdg\ubuntuone\syncdaemon\tritcask
3.Delete them all and restart the Ubuntu One icon.
and now it works for me.
I think it must be some error breaked during the sync and can't resume .
hanging dead. what I do maybe make it a restart.
Linux or do not... there is no dual-boot.