1. PCCheckout (form)<BR>2. AllPCs (table)<BR><BR>The PCCheckout form shows all PC&#039;s checked out and AllPCs are all PC&#039;s, which includes in service which is denoted in this table with a checkbox. When a PC serial number is enterred into the PCcheckout form, a dlookup is done to check to make sure that the serial number entered is an actual serial number in AllPCs. Here is the dlookup statement:<BR><BR>=DLookUp("SerialNumber","AllPCs" ,"SerialNumber = Forms!PCCheckout!SerialNumber")Or is Null<BR><BR>Since this form displays everyone in the company, they may or may not have a pc (which is why the "or is NUll" is needed). This statement only allows for a NULL or a SerialNumber which is in all PC&#039;s, but I also need it to NOT allow a serial number which is inservice, how do I do this? <BR>