14

I've read the MSDN Article about Solution User Options files

The solution user options file is used to store user preference settings, and is created automatically when Visual Studio saves a solution.

But what sort of settings or information is considered a "user preference setting"? I have a weird issue with one of my Solution files I've received from another company and the only fix seems to be periodically deleting the *.suo whenever the problem occurs. Can't figure out what sort of information is actually stored there though. I know it's nothing important, but I'd still like to know and I cannot seem to find the answer.

sab669
  • 3,984
  • 8
  • 38
  • 75

2 Answers2

15

Basically the suo file(i.e., Solution User Options) contains the information related to to a user level customization like breakpoints, bookmarks, Outlining, debugger watches etc.

Also note that if you delete the suo file then Visual Studio will create a new one.

Rahul Tripathi
  • 168,305
  • 31
  • 280
  • 331
  • 1
    Thanks. Are these just things you've noticed in your own experience, or is this actually written somewhere? I couldn't find any hard documentation, just a matter of myself noticing things when I delete the file. I'll accept your answer in a little bit, want to see if anyone else has anything else to say first. – sab669 Feb 05 '16 at 15:28
  • I'd like a definitive answer on this too, but have yet to find one – userSteve Jun 28 '16 at 18:52
  • 1
    I just added it to my .gitignore file in a project because it kept on making these weird and annoying merge conflicts when I made zero changes to the application – Daniel L. VanDenBosch Feb 26 '21 at 14:25
4

Link directly from Microsoft

In addition to what Rahul Tripathi told, suo file also stores

  1. the list of files that are currently open in your editor so that when you relaunch solution after closing it, same files will be shown in the editor to resume our work.
  2. the current active project in the solution, so that when you relaunch it is active again.

To understand better, delete suo file and reopen your project, all the above settings will be lost.

Kartik Podugu
  • 144
  • 1
  • 5
  • and .suo also keeps the current active solution configuration. It is actual to the users of your solution. The most common issue I face with my team, who pull solution out of Source Control - they don`t have the default configuration, which I have. The default configuration is the first alphabetic order in .sln file. – andreyk2 Hohlov May 08 '20 at 15:02