Today our users have started to experience issues with Outlook hanging for a minute or two when replying to emails that include other employees from within our organization. I have tested a few email accounts outside of the organization and Outlook does not hang when replying to them. I also tested OWA and it seems to be working just fine.
Servers: Exchange 2013
Clients: Outlook 2010 and 2013
I do not see any errors on the server that would help point me into the direction of the cause.