taking lot of time and got internal error too.

Telling You the steps.
1.install smf and mybb in the same databse
2.download this converter
http://download.simplemachines.org/i..._converter.zip
3.execute the file convert.php
4.Delete all The tables of Mybb from your databse
5.Install phpbb in the same database
6.Download this mod
http://www.phpbb.com/community/downl...e.php?id=80395
7.Execute convert_smf11.php
8.All done

If you come across any problem then let me know...