Guys We have lost a exchange 2007 sp2 hardware and now requirement to clean this server? what are the options for hard uninstallation? when you don't have exchange box to do it manually?

Remove Exchange 2007 configuration using addsiedit Remove the server’s machine account from all Exchange groups. If the removed server had replicas of Pfs,OAB the replicas will need to be homed onto another Public folder server. Make sure the failed server is not the oab generation server. If the exchange org is in coexisitence then See if the server is listed in routing group connectors.

the only supported method is via Add/Remove Programs i.e. via the Exchange 2007 setup. I assume the server data is still intact in AD. If so, resinstall Exchange to another server with the /recoverserver option and then then unistall gracefully if required. http://technet.microsoft.com/en-us/library/aa998656(EXCHG.80).aspx