Hi there, thanks for coming back to me. I have tried this solution several times but it hasn't worked. I have two workstations running QB Desktop 2019 and only one user can get in at a time. I've run the scan several times to try and cure it so that we can work in multi-user mode but it doesn't make any difference. I've been googling various solutions but cannot fathom out why it now won't work. It was fine when we were running QB Premier 2014 

Any other suggestions would be great, thanks 

Sue