How to fix SQL Server error 5171?

  • Hi, hope you all are doing well.

    I don't know why but I receive an error when I try to open the MDF database. It reads

    xxx.mdf is not a primary database file. (Microsoft SQL Server, Error: 5171)

    I searched about this error message on Google and found this article - semnaitik.com/troubleshoot-microsoft-sql-server-error-5171/

    A couple of tricks have been shared in the article, but they didn't work for me. Even I used a free MDF File Viewer tool that didn't show anything in the file. Is the file corrupted? How can I open this file again? Please help me.

    Thanks.

  • Should there be more files? Please give us the exact steps you are following when you get that error message. Are you restoring/attaching/doing something else?

  • The designation of a file as .mdf or .ldf or .ndf is arbitrary and by convention. There isn't any reason you must have the files names with these extensions. I bring this up as someone could name the secondary data files for a database as .mdf. Or log files.

    If you are getting this, you have one of a couple situations. First, you are missing some files and need to find them. The primary database file is needed to open a database. If you are attaching, then you need to find the other files.

    If this is an existing database and this just appeared, you likely have corruption. There are tools, but if this is important, I'd contact MS Support for help. If you have backups, restore a few immediately and ensure they are able to be restored.

Viewing 4 posts - 1 through 3 (of 3 total)

You must be logged in to reply to this topic. Login to reply