Can you better explain your question, as i cannot understand it.
Also, I cannot help deciphir any syntax errors in your formula, if that is a problem as its all written on one long line
I suggest that you write your formuals vertically like this
URLRoot() & "db/" & [_DBID_PURCHASE_ORDERS] & "?a=API_GenAddRecordForm"
& "&_fid_34=" & URLEncode ([Requisition items])
& "&_fid_10=" & URLEncode ([Purchase Authority])& "&_fid_9=" & URLEncode ([Descrition])
& "&_fid_11=" & URLEncode ([Contract #])
& "&_fid_73=" & URLEncode ([Vendor])
& "&_fid_18=" & URLEncode ([Voucher #])
& "&_fid_19=" & URLEncode ([Voucher Date])
& "&_fid_14=" & URLEncode ([Authorized By])
& "&_fid_15=" & URLEncode ([Authorization Date])
& "&_fid_12=" & URLEncode ([Requested By])
&"&_fid_54=" & URLEncode ([Creation Date])
& "&_fid_90=" & URLEncode ([Order #])
& "&_fid_53=" & URLEncode ([Vendor])
&"&z=" & Rurl()
Please explain what the symptoms of the problem are. Do you have a syntax error? or what is not working.
Also out of the blue you mention a PO table. Does that table have a relationship to any of your other tables.?