No idea what that message means.
Should post code or db for analysis. See instructions at bottom of my post.
How to attach file: http://www.accessforums.net/showthread.php?t=70301 To provide db: copy, remove confidential data, run compact & repair, zip w/Windows Compression.
You are using Macro Code
Try this code
After Entering Code convert the combo to text it will better for you because if you type 12 and you have already 1280 it will show automatic 1280 so for the specific record use textbox instead of combo box but if you are using drop down to search then its ok
replace Your Data source where is "ID"
In my experience, this has always been corruption. I've fixed it by creating a new empty database and importing all the objects from the bad DB.