Thank you very much - your advice worked, Willy. Restarted Windows Repair after disabling Anti Virus and restarting. It ran straight through the 37 repairs in about 45 minutes or so. Previously, it stalled at #17 of 37. Below is the relevant (I hope!) part of the 1st (failed) repair log:
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17 - Repair Windows Updates
Start (22/03/2015 14:15:53)
Running Repair Under Current User Account
Running Repair Under System Account
The current repair has failed to start for over 30 sec.
Trying Again....
Running Repair Under System Account
The current repair has failed to start for over 30 sec.
Trying Again....
Running Repair Under System Account
The current repair has failed to start for over 30 sec.
Trying Again....
Running Repair Under System Account
Setting Windows Updates Files That Are In Use To Be Removed At Next Boot.
Done (22/03/2015 14:19:53)
Done, but failed, at (22/03/2015 14:19:53)
Total Repair Time: 00:22:14
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