Register Information Store Service (Exchange 2010)

I had to uninstall Exchange 2007, but for some reason it didn't remove the information store service. When I installed Exchange 2010 (without realizing that there was an existing MSExchangeIS service) it didn't overwrite it.

Now the Information Store won't start because it points to the old Exch2007 store.exe file.

I have used sc delete to remove the service, but am wondering if anyone knows how i could register a new service for MSExchangeIS to point to the Exchange 2010 store.exe.

I have tried sc create msexchangeis c:\exchange\bin\store.exe but that doesn't seem to do anything.

HELP! Thanks!