The connection was dropped during the transmission. This is quite often identified with networking or system administration misconfigurations or downtime.

Causes

• Typical network connection issue
• Downtime of exchange server

Fixes

Step 1: Transient Error

This can be a transient error, but if the error continues further, then you need to analyse your network devices like router, network card.

Step 2: Local Internet Connection

Check your computer local internet connection, after confirming no local network issue exist, audit conceivable server network related issue.