if you are building your own security for your database you'd have to do a dlookup function to find the PK of the record then bring up your form based that PK
for instance if you had this:
Code:
tblLogins
PK User Pass
1 AAAA booger
2 BBBB brain
When someone typed in a user of AAAA with the correct password in your ON CLICK event of the the button that completes the login you would have
dim iPK as long
ipk = dlookup("[PK]", "tblLogins", "[User] = '" & forms!frmLogin!User & "' AND [Pass] = '" & forms!frmlogin!User & "'")
The dlookup would retreive the PK then you just have to base your opened form on the PK you just looked up.