thanks Tamar

In this instance the problem goes away when the application is closed and restarted.

Also a buffered append blank can take up to 10 seconds on a different table that on all other 9 systems takes approx one second. I've even backed up my app including data from their machine & installed on a virtual machine of similar spec. and it only takes a second to do the append.

After reading all the thoughts on the other thread you pointed me to I think some error trapping does seem the best way to go.

The user is using the Knowhow to look after their computer, they have checked out the machine but say it checks out fine, although they did find as I had already pointed that the internet connection kept dropping out. They apparently sorted this out.

The iceing on the cake is that the machine in question is using WinXP 64bit. Ouch.

I'm guessing that there is either some form of backup installed like Mozy or shadow copying.

Many thanks for the pointers, always much appreciated