This video illustrates how to update a pre-10.5.4 Symantec Messaging Gateway from the command line.
Any SMG update can be executed using the three command line interface command demonstrated in this video.
WARNING: Updating older SMG gateways now is critically important because communication with Symantec's Update Servers will be impossible without SHA-2 certificates after June 30, 2016. Older gateways do not have SHA-2 certificates and there will be no way to update older gateways after June 30, 2016.
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