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Error: "550 5.7.1
... Relaying denied. IP name possibly forged [195.xxx.xxx.xxx]"
The IP redirects to a DNS name which in turn redirects to another IP, for example: a reverse lookup of 10.0.0.1 gives test.infomaniak.ch but test.infomaniak.ch points to 192.168.0.1, resulting in the "IP name possibly forged" message; you will therefore need to check this with whoever is in charge of your IP address.
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