Yes. I know. A thread started by Methusalem ages ago. But the same thing happened to me here in Germany today for the first time.
Background: I use a mail server operated by a very small entity, embedded in a server farm. People using Pegasus Mail here in our LAN were all unable to send mail today, port 25 and 587 were blocked. Even no sign of attempts to send something visible on the server itself. Other users living somewhere else had no problems to send mail. So, the reason must be local, at least on the path between here and the server.
Enjoying the luxury of two different internet providers I switched my PC's gateway from the usually used German Telekom to the one provided by our cable-TV provider. All mails sent. Hmmm.
So, the blocking stone must be the Telekom line. Some googulation showed that Telekom has the habit of blocking ports 25 and 587 when they think that there is a spam source on the other end, but usually only after an announcement. None such here.
While reading several articles, the keyword "list of reliable mail servers" hit my eye. I remembered that I had had the exactly same problem after first installing the W922V routers provided by Telekom when we switched to VDSL here. I had to add the IP of our mail server manually at that time.
Open the router's setup, list of reliable mail servers - where has my entry gone? Closer inspection showed a line: last update Oct 18, 2017. Ahhhhhhhrrrrrgggggg. 'They' can do that remotely. And they overwrote my previous manual entry.
Re-entering the IP in the list solved the problem. Phew. No search for a SPAM source needed. Sigh.
HTH
<p>Yes. I know. A thread started by Methusalem ages ago. But the same thing happened to me here in Germany today for the first time. </p><p>Background: I use a mail server operated by a very small entity, embedded in a server farm. People using Pegasus Mail here in our LAN were all unable to send mail today, port 25 and 587 were blocked. Even no sign of attempts to send something visible on the server itself. Other users living somewhere else had no problems to send mail. So, the reason must be local, at least on the path between here and the server.
</p><p>Enjoying the luxury of two different internet providers I switched my PC's gateway from the usually used German Telekom to the one provided by our cable-TV provider. All mails sent. Hmmm.&nbsp;</p><p>So, the blocking stone must be the Telekom line. Some googulation showed that Telekom has the habit of blocking ports 25 and 587 when they think that there is a spam source on the other end, but usually only after an announcement. None such here.
</p><p>While reading several articles, the keyword "list of reliable mail servers" hit my eye. I remembered that I had had the exactly same problem after first installing the W922V routers provided by Telekom when we switched to VDSL here. I had to add the IP of our mail server manually at that time. </p><p>Open the router's setup, list of reliable mail servers - where has my entry gone? Closer inspection showed a line: last update Oct 18, 2017. Ahhhhhhhrrrrrgggggg. <i>'They'</i> can do that remotely. And <i>they</i> <i>overwrote my previous manual entry</i>.&nbsp;</p><p>Re-entering the IP&nbsp; in the list solved the problem. Phew. No search for a SPAM source needed. Sigh. </p><p>&nbsp;</p><p>HTH
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