Sometimes you require to run two versions of any software on a same machine. To run OpenERP with two different versions, you can have issues even if you try to use different browsers or windows at the same time.

To run OpenERP 6.1 and 7.0 versions on my machine, I installed them and tried that same way mentioned above. And it gives error!

Not Found

The requested URL was not found on the server.

If you entered the URL manually please check your spelling and try again.

Somehow I could managed to come out of this problem. And the solution is Services.

1. Simply Go to the Services of your system.

   Control Panel-->Administrative Tools-->Services

or simply type Services.

2. Go to Properties by right clicking set the Startup Type: to Manual from Automatic for both versions.

3. Whichever version you need to run just start that service.

Remember: install the versions in different drives.