LAN connectivity question

[Tom]

Periodically my PC &/or wireless router will lose connectivity to the LAN (I'm on cable). The result will be "Unable to find to xxx" messages. However, my email will continue to function in both directions. Tonight it occurred to me that I haven't seen any emails for most of the day, although I can browse just fine. If I try to retrieve email I get "unable to connect to xxx server" messages. This is the opposite of the condition I see most often.

I rebooted the cable modem and router, but still don't have email. Next step will be to try rebooting the PC, although the email server itself might be down of course.

My question is .... how is it possible to lose connectivity for browsing but not email or vice versa?

 

[Tom]

Sure enough, rebooting the PC brought email connectivity back and there were approx 100 emails waiting for me. I'm still puzzled why I was able to browse while email wasn't working  ???

 

[Karl]

Tom,

Your email uses dedicated POP (for receiving) and SMTP (for sending) servers for emails; your browser is quite seperate from them, so it's entirely possible for one to work and the other not.

 

[Tom]

OK thanks Karl. Just for clarification, I have 4 POP email boxes being scanned on 3 different ISPs, although they all use the same SMTP server for sending. So, would you expect all 4 (3) to quit receiving at the same time? Or are you saying it's the email app that wasn't working, although I'd restarted the app twice in an attempt to get it to retrieve email?

 

[John From Detroit]

Many diffferent services use a specific port on the TCP/IP stack,  It's likely that the E-Mail port was what was farkled and by re-booting you reset all the TCP/IP ports to their startup condition.

Also, likely not the problem but you should do a spy and mal-ware scans (Anti-spy and anti-virus) ASAP just to be safe.

If your computer is Windows... Occasional reboots are a very good thing

 

[Tom]

Thanks John.

If your computer is Windows... Occasional reboots are a very good thing

Sure would be nice if we didn't need to say that one of these days. XP is much better in that respect than some prior rev(s) of Windows, but I find myself doing more occasional reboots than I'd like.

 

[Smoky]

Tom:

When I was back in Maryland on Comcast Cable, those things happened to me on a weekly basis.  Interestingly I have never had that problem on Direcway.

 

[Tom]

When I was back in Maryland on Comcast Cable, those things happened to me on a weekly basis.

Interesting Smoky, because I'm on Comcast. On a number of occasions I've been convinved there was something going on at their service end. Sometimes, by the time I've rebooted, unplugged/reset modem and router a number of times, when things suddenly start working I'm left wondering where the problem really was to begin with.

 

[Karl]

Tom,

The POP (or POP3) server is for receiving email; the SMTP server is for sending. It's possible that only one POP server is experiencing trouble, so you wouldn't be able to receive email for that account, but would for the others. I find it strange that you use only one SMTP server for multiple accounts UNLESS you're talking about seperate mailboxes for the same account. Seperate email accounts use seperate servers. Example: my Gmail account uses SMTP.GMAIL.COM for sending; POP.GMAIL.COM for receiving, DirecWay uses SMTP.DIRECWAY.COM for sending; POP3.DIRECWAY.COM for receiving, while my Escapees uses MAIL.ESCAPEES.COM. for both sending AND receiving. Ports used for Escapees and DirecWay are both 25 for SMTP and 110 for POP; Gmail uses 465 for SMTP and 995 for POP.

 

[Ned]

There is no reason to use other than one SMTP server to send mail for all accounts.  I use the direcway SMTP server to send all of my mail (for 8 accounts at present).  The only advantage of using the SMTP server associated with a POP3 email account is that mail to accounts on the same server will arrive faster, perhaps saving a few seconds

An advantage to using a single authenticated SMTP server for all email sending is to avoid having to change the SMTP server when connecting to the internet via different ISPs.  The Escapees server is a good choice for that, as is GMail.  GMail is the more secure as it uses SSL.

 

[Karl]

Quite true Ned, but I've had more problems with the Escapees servers than any others. Guess I'll opt for GMAIL for my SMTP.

 

[Tom]

The POP (or POP3) server is for receiving email; the SMTP server is for sending.

Understood and thought that's what I said, but just re-read it and realized I wasn't clear.

It's possible that only one POP server is experiencing trouble, so you wouldn't be able to receive email for that account, but would for the others.

When this happened, I couldn't receive email from any of the accounts.

I find it strange that you use only one SMTP server for multiple accounts UNLESS you're talking about seperate mailboxes for the same account.

As I said, 4 accounts on 3 ISPs (I should say 4 addresses on 3 ISPs or 4 addresses on 3 accounts). I just checked the server settings again and confirmed the same SMTP server is used for all accounts/addresses and all use port 25. IIRC when I previously set up Mozilla Thunderbird to retrieve mail, it told me that only one SMTP server is needed, so it's set up as a default SMTP server. I recall the same thing with my prior mail app. This works whether I'm hooked up to cable, Direcway, cell/GPRS card, or land line. FWIW all POP addresses use port 110, like yours.

 

[Ned]

Thunderbird will let you set up multiple SMTP servers and you can change them at any time.  It's a nice feature.  I have a button on my toolbar that says "Select SMTP!" but it may be a feature of ver. 1.5 which isn't released yet.

As for why you could browse yet not get email, it could be a problem in the TCP/IP stack or the firewall.  Since a reboot fixed it, it was obviously in software.  Chalk it up to the "perversity of the inanimate object"

 

[Tom]

Don't have that button Ned. The only time I could think I might need it is if one SMTP server was down.

 

[Gary RV_Wizard]

Tom,
If all your email access stops working but browsing remains active, it seems most likely that your email software lost sight of the internet connection somehow.  The connection exists but the email software doesn't recognise it OR gets a "not OK" resp[onse from Windows when it tries to access it.  That could be a glitch in the email software, or could be a problem with the incoming mail port (usually port 25 for pop mail). OUtbound mail uses a different port to contact the SMTP server, so it is possible for one to work but not the other (and Browsing is separate from both if those).

Since you needed to re-boot to restore the email access, I would guess a port problem, which might include a firewall problem.

 

[blueblood]

I'm sure (or at least very doubtful) that this isn't your problem but just for info. In this area, we have what look like at least three different ISP's if one looks at addresses i.e two cable companies, one phone company, etc. However, I was working on a web development and had a problem that went across all three so I thought it was me. For insurance, I hooked up my Verizon cell phone and ran it on National Access and it worked. I went to the "ISP's" and discovered they all used the same real ISP who maintained a seperate data base for them.

 

[Tom]

OK thanks Gary, that makes sense. Usually when this happens, it's the browser hat quits being able to connect and email works fine. Occasionally, like last night, it was the other way around. It sure leaves me scratching my head on occasions.

 

[Tom]

Interesting Leo, thanks.

 

[caltex]

Tom, just so you know that you are not alone.  I have experienced the same problem on Sprint DSL, using an Apple computer.  I use Safari and Entourage for browser and e-mail. When that happened, the problem was solved by restarting the individual application.  The problem has gone away since Sprint fixed my DSL.

 

[Tom]

Thanks Robert. I recall you mentioned it once before. I guess I can't blame it all on Billy in Redmond.

Do you know what Sprint did to fix the DSL?