Question : Can't open any more databases. (Error 3048)

I have created a master report with many subreports and associated queries.

Purpose is to number the pages sequentially for a report package.  

Worked great until I hit a wall -- a jet error message "Can't open any more databases. (Error 3048)".  Help says to close a database and try again, but I don't understand this at all.

Would appreciate any help to correct this or to advise an alternative
approach.

Thanks in advance for helping a newbie.

Answer : Can't open any more databases. (Error 3048)

Try either indexing the queries or connecting straight to the tables to use less memory....