[Koha] Koha login error

[MASTeR Library]

Dear sri, koha when logging in the following error is coming what should be
done to fix this.
n error has occurred!*Error 500*This message may have been caused by any of
the following reasons:

   - You made use of an external link to an item that is no longer available
   - You followed an outdated link e.g. from a search engine or a bookmark
   - You tried to access a page that needs authentication
   - An internal link in the client is broken and the page does not exist

What's next?

   - Use top menu bar to navigate to another part of Koha.
   - To report a broken link or any other issue, please contact the Koha
   administrator. Send email <masterlibrary%40mamcet.com>