Jun 15, 2018 10:12 AM|DA924|LINK
Yes, it looks like Localdb is not installed on the machine. Also as the connectionstring stands now, the MDF file should be in C:\users\uersname is where it should be located where Localdb will look for it. Or the connectionstring must give the file path
to where the MDF file is located.
Take not that the MDF file should be attached to the database engine, if it is to be ever used in a multi user environment, becuase Localdb is only a single user instance meaning only one user can have the MDF file open at any given time.