From time to time TFS (Team Foundation Server) goes down in work. It can be frustrating but I always just keep coding. This can cause problems as TFS will not be aware of your code changes and when the sever comes back online you won’t be able to just check your code changes in as normal.
However there is a handy solution, when TFS comes back online right click on your solution. In Visual Studio there should be an option “Go Online”, click that and it will list all the files you have changed offline and check them in for you while bringing the solution back online.