2 Year Ago
Symptoms: User tries to open network shared Excel sheet using Office 2003. It runs extremely slow, especialy when file size exceeds 1Mbyte.
There is known "bug" of Office 2003 (documented in Microsoft KB - http://support.microsoft.com/kb/2570623) when it opens shared files extremely slow (not always, time to time).
There is FileValidation feature enalbed by default for all Office 2003 applications. When disabled it makes this issue to disappear.
Another option - upgrade to Office 2007 or 2010 - they have smarter FileValidation algorythms which don't affect PCs even in slow speed networking conditions.