Can't install/update ReSharper: Failed to download and save packages. The underlying connection was closed

Problem

ReSharper fails to update with

11:45:41.572 |I| ReadyToInstallPage | 11:45:30.314 ReSharperPlatformVs17_7ea0eaa5: Failed to download and save packages. 
The underlying connection was closed: An unexpected error occurred on a send. 
Authentication failed because the remote party has closed the transport stream. 
Unable to connect to the remote server An operation on a socket could not be performed because the system lacked sufficient buffer space or because a queue was full

Cause

There could be some network restrictions, like proxy, antivirus etc, that block the web installer connection.

Resolution

Use the offline installer in this case.

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Can't install ReSharper: “The remote server returned an error: (403) Forbidden” error

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