save as dropdown list not showing files

<FONT face="Arial Unicode MS" size=3><SPAN style="FONT-SIZE: 12pt; FONT-FAMILY: 'Arial Unicode MS'; mso-fareast-font-family: 'Times New Roman'; mso-bidi-font-family: 'Times New Roman'">When I do a ‘file save as’ and type the name of the file, starting with ‘s’ or ‘som’ the dropdown list of the files in that folder starting with s, or (som) doesn’t show up. A file named someone.doc exists but doesn’t show until I try to save it and then I get “this file exists” following me? The save as dropdown list doesn’t show. This happened before SP2 which I now have. What happened?