now i'am installed # Multi-Domains # Domain-Mapping # WHMCS

now i'am installed
# Multi-Domains
# Domain-Mapping
# WHMCS MU Provisioning
# WHMCS WP Integration
# Pro Sites
every thing run correctly
but when user create site his can't login to wp-admin area on main site .
i give users on my main blog Permissions to create articles .
now users can't login to wp-admin area on my blog .
and i need when visitor signup on any blog under network can login with any other blog on network " just one account for any blog under my network " .