10

Basically, I had a project that was written with Visual Studio 2010 Express in C#, I then tried out using Visual Studio 2012 Express with that file, and now VS2010 says:

"The selected file is a solution file, but was created by a newer version of this application and cannot be opened."

Now when I had looked up about this, Microsoft said that you can still use 2010 if you do not use anything that was VS2012 specific. Well, I had tried out the built in Testing that is in the VS2012, and that was the only thing that was VS2012 specific, but deleting that from my project (the Testing project), still left it saying that it was created by a newer version.

So, how do you make a VS2010 solution that VS2012 modified work with VS2010 again?

Xantham
  • 1,829
  • 7
  • 24
  • 42
  • 1
    Do you have SP1 for VS 2010 Express? That's required to open VS 2012 modified solutions. – aquinas Sep 19 '12 at 01:09
  • No I did not. This also solved my problem. Actually, when I told it to check for updates, it just told me to start "Windows Update" but in WU I found no mention of the SP (me installing it or whatnot). I had to search MS's website to find the link to the Service Pack. I actually initially installed VS on this computer from their website about a year after the release of the service pack, so I am a bit perplexed why they did not update their download of VS2010 C# Express on their website or make a clear mention of the SP1. – Xantham Sep 19 '12 at 18:51

5 Answers5

12

SP1 for VS 2010 is required to open VS 2012 modified solutions.

aquinas
  • 23,318
  • 5
  • 58
  • 81
4

Try this out:

http://vsprojectconverter.codeplex.com/

Personally I've never used it but I have it marked as a tool to use if I run into issues. Hope it helps!

Nate-Wilkins
  • 5,364
  • 4
  • 46
  • 61
  • 2
    This seems to work for me. Thank you for the answer. I do find it odd that MS clearly says that you can use 2010 and 2012 on the same project, yet a 2010 created solution seemed to prove them incorrect. – Xantham Sep 19 '12 at 00:15
  • @Xantham, the say 2010sp1 and 2012 :) – Sebastian Mar 01 '13 at 10:56
0

This probably isn't the kind of answer you are looking for, but it has worked for me in the past for compatibility issues and such, so it's worth mentioning. If your project isn't too complicated, you can create a new project then copy and paste everything across, starting with form controls, and then moving to the code. It's a sloppy solution that doesn't scale well, but sometimes nothing else seems to work.

Void Star
  • 2,401
  • 4
  • 32
  • 57
  • 1
    Yeah, I know that is always an option, but I wanted to know if there was a more elegant solution before I had to do that. – Xantham Sep 19 '12 at 00:13
0

The response here by Andrew.Wu is very comprehensive http://social.msdn.microsoft.com/Forums/en-US/vssetup/thread/fc763995-beed-4287-97de-6e47d3e87865 and details steps to take to solve the problem

Sameer Alibhai
  • 3,092
  • 4
  • 36
  • 36
0

very old...but hope it can help someone...

Step 1: Go to your project location where the project's sln file is kept and then Right-click on it, choose "Properties". Uncheck "Read Only" as like given below:

Step 2: Again Go to the location where the project's sln file is kept and then Right-click on it to open it with notepad and change the "Microsoft Visual Studio Solution File, Format Version 12.00" to "Microsoft Visual Studio Solution File, Format Version 11.00" on the file.

you can change also the "Visual Studio 2012" to 2010

batsheva
  • 2,175
  • 1
  • 20
  • 32