asp.net mvc - Delete .mdf file from app_data causes exception cannot attach the file as database

Question

I am building a web application using VS 2012 MVC4 code first. In order to recreate the .mdf file after I changed the model, I manually deleted the file from the app_data directory in VS. I have done this a few times before without any problem.

Now I receive an exception:

The underlying provider failed on Open. ==> Cannot attach the file MYDB.mdf as database 'MYDB'.

I will appreciate your help on how to recreate the .mdf file.

Thank you!

Answer 1

That what fixed it for me, From Package Manager Console run these commands:

  sqllocaldb.exe stop v11.0
  sqllocaldb.exe delete v11.0

And then:

  Update-Database