If you face problems with Downloading attachments from Exchange (EWA) With SSL enabled. You can try everything but easiest would be this. Apply this registry key into server
1. Goto HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings
2. On the Edit menu, click Add Value, and then add the following registry values: "BypassSSLNoCacheCheck"=Dword:00000001