Exchange 2010: A previous version of Exchange Server..

Receiving the message ‘a previous version of exchange server is already installed on this machine’ when trying to install Microsoft Exchange Server 2010? Logo_MsExchange2010

I’m just upgrading one of our Microsoft Exchange 2007 Servers to Microsoft Exchange Server 2010. I’ve decided to first remove the Exchange 2007 Server and then install the 2010 Version. Well, if you should ever choose the same path, you’ll have to pass a few hurdles… After following the instructions in the links provided below, i finally was able to remove Microsoft Exchange Server 2007. When i then started Microsoft Exchange 2010 Server Setup, i got the message:


Setup.exe – A previous version of Exchange Server is already installed on this machine.

Well, since this Version of Exchange is pretty new and Google nor other search machines give you good results about this issue, i decided to not spend to much time searching the internet but opened the registry editor and searched for Exchange in the HKLM/Software Key.. What i’ve found:



Rename this Key to _Exchange, start setup.exe again and you’ll be fine ..




This Server is the Source for a Send Connector

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