Port 25: No route to host

I get this error message whenever I try to send a message using my smtp server. This was working till morning. Suddently, this error has popped up.

What should I do? Can this be because of any packages that I've installed/removed? I use Evolution for email, and RH-9 2.4.20-8 Linux kernel.


-Dhruv.

Might be the other computer, try pinging it.

It's most likely that it can't be reached (as in no computers to route the message through)

well, that usually mean your routing isn't correct, but if you can post here, I assume your other internet services are working.
Silly idea, but often, ISP blocks port 25 to external to make sure their client aren't spamming... maybe your ISP is now blocking this port? Have you tried to scan your computer from the outside (with something running on port 25)?

<QUOTE>
well, that usually mean your routing isn't correct, but if you can post here, I assume your other internet services are working.
Silly idea, but often, ISP blocks port 25 to external to make sure their client aren't spamming... maybe your ISP is now blocking this port? Have you tried to scan your computer from the outside (with something running on port 25)?
</QUOTE>


Yes, I can even receive mail! I just can not seem to be able to send it using either of my smtp server providers!

From another reply ->
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Anyways, I re-installed linux, and with the default kernel it works fine but when I re-compile the kernel (2.4.20-8), the the same thing happens? The most amazing thing is that I have been using this same re-compiled kernel (with the same config file) for the past soooo many months, and the error has popped up just a few days ago.

Maybe this has something to do with the filewall config? Maybe, but sonce it was working perfectly until a few days ago, I can not be sure, and + the fact that the default kernel does not give these problems???

The reason I'm using the re-compiled kernel is that the default can not detect fully my 640MB of RAM. It just detects 628MB? Any ideas?



-Dhruv.

<QUOTE>
Might be the other computer, try pinging it.

It's most likely that it can't be reached (as in no computers to route the message through)
</QUOTE>

I did, and the ping is successful! That's what i can't figure out.

Anyways, I re-installed linux, and with the default kernel it works fine but when I re-compile the kernel (2.4.20-8), the the same thing happens? The most amazing thing is that I have been using this same re-compiled kernel (with the same config file) for the past soooo many months, and the error has popped up just a few days ago.

-Dhruv.