Another program is being installed. Please wait until that installation is complete, and then try installing this software again.

Problem

Today I planned to install ASP.NET MVC 4.0 beta for Visual Studio 2010. When I started the installation, it gave me an error message saying:

"Another program is being installed. Please wait until that installation is complete, 
and then try installing this software again."

At that time I did not have any installation running. Then, I restarted my computer as re-boot can be a magical treatment for many Windows issues. But in this case it did not work and same error continues to come.

After doing some research I solved this issue. FYI: I was using a 64 bit Windows 7 Operating System.

Solution

1. From Start menu run services.msc
2. Find WindowsInstaller from the services link.
3. If you see it is started and set to automatic, disable it.
4. Re-start your pc.
5. Again go to services.msc.
6. Set WindowsInstaller to start as "Manual".
7. Now start your installation. 

In my case the above solution worked. Hope it will do for you too.