I need to create folders naming from 'folder1 to folder50' into folder named "Main folder".

Hi,

Next time you should post your Documentum related questions in https://community.emc.com/community/edn/documentum area.

There is no automatic way to do this, but you can do it with DQL and with MS Excel (to complete the numbering). A DQL for creating a folder:

create dm_folder object set object_name='folder1', link '/Main folder'

If you create a file with the 50 DQLs, you can use idql tool to run it (idql needs 'go' command after each dql command to run it, don't forget this).