Sharepoint 2010. Web Part Page Not Adding?

Question

SharePoint

When you try to create a web part page in Sharepoit Designer, you get an error:
"Could not complete this operation when adding a web part page"
And if you try to create it through the web interface, it gives an undefined error.
If anyone has come across - help with advice on what to do.
Thank you!

Answer 1

First, include the full text of the errors ( How To ). If it is not clear from the full text where the error comes from, post the text/screenshot here.