Error Message

I tranferred my site from one server to another and I am now receiving this message sometimes, both when trying to access pages and in the widgets when viewing profiles of members.  It doesn't happen all the time and the problem can be corrected by doing a page refresh, but it does create problems especially after typing a message or a blog and receiving it.  Does anyone know what I can do about it?

 

Welcome to Elgg.

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Elgg couldn't connect to the database using the given credentials.