Thanks for the replies:
I am using edit + paste and the field is a drop down look- up values from the "Accounts" table.
In the meantime, by process of elimination, I managed to find the offending field -->"Terms" - a text field.
When I remove the field from the form, the contents of the "Account" field is pasted. IT WORKS!
After reinserting the "Terms" field back on the form but in another location, it still works.
Odd - just wondering why this would happen.
Zed