I get the following error when I try to invite users. Please help.
Event Type: Error
Event Source: Windows SharePoint Services 3
Event Category: General
Event ID: 6644
Time: 10:32:48 AM
Event manager error: Could not load file or assembly 'InvitationExpireDate, Version=18.104.22.168, Culture=neutral, PublicKeyToken=9f4da00116c38ec5' or one of its dependencies. The system cannot find the file specified.
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