Hi Graham, 

Thanks for using Community Hub. 

There are a few reason why this may have happened:

• There's no free disk space on the hard drive
• The data path in the Company file is the incorrect format
• A folder in the data path doesn't exist
• The files are locked open
• You don't have sufficient access rights
• The files are marked as hidden
• The backup is corrupt
• Antivirus software is restricting access
• A non-standard character in the file name

These error can be easily resolved by following the steps in this guide.

Hope this answers your question, if it does click on Verify Answer to let others know too. 

Regards 

Annie 

Sage UKI