We use a shared mailbox at work for my team. All incoming requests (12000 emails a month believe it or not!) for my team are mailed to this shared mailbox. This mailbox then has seperate folders for each month where we file the emails once we complete the request. The issue we are having is that it is rather cumbersome to try and use the search feature as you can only search one folder at a time with a shared mailbox. At one point I played around with indexing options locally on my machine and was able to go to (within Outlook) Tools -> Instant Search -> Advanced Find -> then select the shared mailbox's inbox and also have the ability to check the 'Include Subfolders' option. This worked great! But I cannot remember how I did it... The 'Include Subfolders' option is greyed out after I received a new machine and I don't have the old one to contrast and compare. Whatever I did last time it was done locally and not on the Exchange server. I believe that I was able to somehow index the shared mailbox even though it is stored on the Exchange server, is there a way to create an .ost file for a shared mailbox so that we would have a copy locally to search? I am open to any solutions that would enable this for my team.

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