SB Error: Module with instance id='q1sic24ochf' does not exists

Hello,

I have sitebuilder server with many users and sites, but one of them has problem. When he tries to login there is an error:

Internal SiteBuilder error.
File: /usr/local/sitebuilder/include/SB/Site/ModuleInstancesList.php; Line: 71
Message: Module with instance id='q1sic24ochf' does not exists.; Code: 0

Any ideas? what can I do with it?

Please help,

David