Having left Windows Update running for a day and a night - over 24 hours - it still displays "Checking for updates..." with the progress bar happily drifting from left to right.
I was advised (elsewhere to:
Disconnect from internet
Restart PC
Manually run 1st install (KB3102810)
Restart PC
Run...
boot issues
error 7034
event log
hotfix
install failure
internet connectivity
kb3102810
kb947821
manual install
pause updates
progress bar
software update
system update
troubleshooting
update
updates
user assistance
windows 7
windows modules installer
windows support