Binary format of the specified custom attribute was invalid
One of the user was moving bulk emails using OnePlaceMail (Desktop version) all of sudden OnePlaceMail crashed.
After restarting the Outlook, users started to get the error message "Binary format of the specified custom attribute was invalid". Now OnePlaceMail is not available as add-in.
We un-install and re-install OnePlaceMail (Desktop) multiple times but the error persis. Please help us in resolving this problem.
AdminSupport (Admin, OnePlace Solutions) commented
Thank you for your comment. I have responded to your support request via email.
For reference, this looks to be an issue with the .NET Framework. Please see if repairing the .NET Framework resolves the issue.
Microsoft Repair Tool: https://www.microsoft.com/en-us/download/details.aspx?id=30135