What does the performance look like when you run just the SQL part of the SELECT statement?
<pre>select Phone, Member, FullName, TransAmount, TransType, WOAmount, WOCode, WODate from cnvWriteOff_SWI a
where not exists (select * from cnvSerord_SWI b
where a.Phone = b.Phone
and a.Member = b.Member)</pre>
You may have an indexing problem that you need to look for. If this recordset returns quickly then it is going to be an Excel problem.