where do we find the .ost file in Exchange server 2007 please help me thanks

on machine, where outlook 2007 installed %userprofile%\AppData\Local\Microsoft\Outlook

It is not on the Exchange server. It is on the client side. It is part of your outlook configuration. In Outlook 2007: On the Tools menu, click Options, click the Mail Setup tab, and then click E-mail Accounts. In the Account Settings window, click the Data Files tab. You will see the OST file details there Santhosh Sivarajan | MCTS, MCSE (W2K3/W2K/NT4), MCSA (W2K3/W2K/MSG), CCNA, Network+ Houston, TX http://blogs.sivarajan.com/ http://publications.sivarajan.com/ This posting is provided "AS IS" with no warranties, and confers no rights.

and if you using Outlook 2007 in not Cached Exchange Mode only

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