Yes, that contact from i tried to create appointent was an AD contact.
I use “hibrid” solution. Contacts are stored in sql and list AD contacts for internal informations. I also use AD groups as distribution lists and it is also stored in sql, but the group names come from AD.
What are these limitations?
I was make a backup and delete the problem lines, then make a restore.
What is the name of the column, that store GUID parameter to the events participants?
What can i do to avoid this error when i use AD contacts?