We have users with outlook 2003 and exchange 2007 running in cache mode. When they attemp to open attachments- docs, pdfs etc they complain it takes forever even when the file is only 1-3mbs. Is this because they are running in cache moe? the exchangr server is in the same site as them. Is the outlook OST file generated because of cache mode?

Yes, the OST file is generated when cached mode is turned on and contains a copy of the mailbox contents held in the Exchange Server Information Store. It is unusual for opening attachments to be slow with cached mode because the user is working with a local copy. Some things to look at: 1. Location of OST file. Is it local to the workstation or on a network share? It shouldn't be on a network share. 2. Clear the Outlook temporary file cache (see http://www.groovypost.com/howto/microsoft/outlook/find-the-microsoft-outlook-temporary-olk-folder/) Tony

Restore corrupted OST file using Restore Microsoft OST Tools. OST recovery Tool also converts to Outlook formats like (97, 98, 2000, 2002, 2003, 2005, and 2007). http://www.convertostpst.com/