When trying to run backup the following message appears: Last backup did not complete successfully. [More info.] Windows failed while trying to read from the shadow copy on one of the volumes being backed up. Please check in the events log for any relevant errors. I've checked in the events log but I don't quite know how to spot any errors. My computer is an Acer using Windows7 64 bit system.

Hi Seoirse, I have seen this problem occur before where there has been an infected file on the shadow copy. Explanation: Assuming your host machine becomes infected with a virus and the virus is located within a location that is subject to shadow copy, the shadow copy will retain the file after your virus protection deletes it. The antivirus will place a lock on these files and they must be removed by the antivirus software before a backup can proceed. You may also wish to investigate possibilities as per MS Article http://support.microsoft.com/default.aspx/kb/973455/ Best Of Luck! Martin