Snapshot aborted not sure if it completed


Just got an error whilst creating a snapshot

"An unknown response returned from Snapshot backup attempt. Aborting. Double check Snapshot settings."

Not sure what settings to check as they are the same for all my sites.

I know the hosting server the website is on, is slow...When I try to export copy of database it always crashes!!

Hence one of the reasons for wanting to move the site away from current hosting company.

Any advice or help as to what the error could be for, would be most helpful.