What he's asking you to do is build your string in a seperate variable and print it to the debug window first so you can get a look at what's actually being fed to DoCmd.RunSQL
Change
Code:
DoCmd.RunSQL "some sql code here"
to this:
Code:
Dim strSQL As String
strSQL = "some sql code here"
Debug.Print strSQL '<---- Print the string so we can see that it's been built correctly
DoCmd.RunSQL strSQL
And report back what you see in the 'immediate' window. To see the immediate window in your vba editor go to View -> Immediate Window. For example it should spit something out that looks something like this:
Code:
Update tblRequests Set tblRequests.[cboEstimateStatus] = 'Pending Request' where tblRequests.[txtProjectNumber] = '21201'