We upgraded from 2008 to 2010 Visual Studio and I am trying to create a .rpt file and everytime I create the .rpt file it is renamed to a .mht file and I get the Crystal Rep
Crystal Reports is now owned by SAP, and since SAP couldn't deliver Crystal Reports Visual Studio integration according to Microsoft's deadline for every possible release, it was dropped out of Visual Studio. It's now a separate, yet free download provided by SAP.
You can download the Crystal Reports Visual Studio version over here.
However, as of now it's Beta 2. So you should check out the release notes provided as a PDF download on the same page. There are a lot of tricks and issues to pay attention to. Especially for 64 bit systems and non-english Windows versions.
Something worth noting when installing Crystal Reports for Visual Studio 2010 which might not be readily apparent (at least it wasn't for me). I kept installing & reinstalling Crystal Reports, but each time I tried to add a report inside Visual Studio, I got the .mht file that told me to download it. This happened for both the 32- & 64-bit installations.
It occurred to me much later that I've been installing the Redistributable packages (which is meant for deployments to servers & the like) the whole time and not the .exe that supplies the developer tools needed to create reports in Visual Studio.
Make sure to install the right package on the right machines. This link supplies a table with all the available downloads. If you want to design reports inside Visual Studio, click the link in the first column (Install Executable) to download the correct installer.