Tunrip

Yes, we've noticed exactly the same thing, including the subsequent "exceeded the available concurrent connections for your account" message after this problem has occurred enough times. This started on 6th...

It appears to read the list of folders and an error occurs on/after the last entry. When the error occurs it just whacks it in the XML in an invalid...

Thought I'd try restricting the number of items returned by FindFolders using a FolderView with a PageSize of 1. Wondered if this would return the first item before encountering the...

I have posted about this on the Microsoft Q&A forum, as some googling suggested this may help get it spotted by the appropriate team. https://learn.microsoft.com/en-us/answers/questions/1229639/exchange-web-services-ews-findfolders-produces-a-5

It's working for us now internally. Tried at a client site and immediately ran straight into the "Microsoft.Exchange.WebServices.Data.ServiceResponseException: You have exceeded the available concurrent connections for your account." error unfortunately!...

Looked further into the client site still not working and realised this still has the original XML error. Originally at the client site it took an additional 5 days for...

Looks like this is now fully resolved :)