[AccessD] #Name?

Hey All
Can someone explain to me what causes in a textbox on a report
"Total - " & format(me![SumBal],"#,##0.0")
On some machines (all running the same mde program) to display
Total - 123.1
 and others
#Name?

I have checked the regional settings and they all the same.

I think this has been asked before but I could not find anything in the 
archives.

Thanks