We are having continuous problems when opening SDP in IE11 e.g. when replying from ticket to the end-user the message is not sent nor saved in the ticket, sometimes SSO pass-through doesn't work and we need to open the browser once again to get the user authenticated or finally SDP throwing "server errors" pages. In such cases emptying Temporary Internet Files helps, but for a very short time.

Additional comment: users working at the same time on Chrome browser doesn't experience such issues!

/Mar