ISP IMAP acc't(s) send mail problem [solved]

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li'loleme
Posts: 5
Joined: Mon Apr 12, 2021 12:35 pm

ISP IMAP acc't(s) send mail problem [solved]

Post by li'loleme »

Greetings! Long time user of POP Peeper (free) & it has served me well for years.

I have 2 virtually identical Win 7 x64 (up to date) PCs w/ POP Peeper installed. Last week, one PC started giving me the following error when sending an email from any of 3 acc'ts. Gmail IMAP configs on both PCs work fine... only ISP IMAP acc'ts on 1 PC fail.

OS: Windows 7 (x64)
POP Peeper: 5.1.1.0
Webmail: 5.1.0.0
SSL: 1.1.1.7
IMAP: 5.1.1.0
SendMail: 5.1.1.0
PPTweaker: 5.1.1.0
Updater: 1.0.0.0

Program folder: C:\Program Files (x86)\POP Peeper\
Data folder: C:\Users\usernameC\AppData\Roaming\POP Peeper\

--- Error ---
ispname - username [1000: IMAP] ['mobile.ispname.net' (993) SSL: 1] [Smtp: 'mobile.ispname.net' (587) SSL: 1] [oauth: 0] [consec: 1]
- Send Mail: Failed to Verify after EHLO
Server Returned: EHLO [external IP] blocked. Please see https://www.ispname.net/support/interne ... rror-codes for more information. AUP#Out-1080 (#501)

which says "This email account has limited access to send emails based on suspicious activity. Blocks will expire based on the nature of the activity. If you’re a ispname customer, contact us to remove the block".

DEBUG steps.

- Tested BOTH PCs. Only one exhibits this issue.

- Assuming a banned/blocked IP, I tried a MAC clone on my router, pulled a new IP & got the same error... on the same PC.

- Called ISP & verified NO blocks on their end. Jumped thru their "hoops"... send via webmail, etc... passed w/ flying colors. "NOT our problem."

- Uninstalled POP Peeper completely on the 'problem' PC & removed ALL profile data. Reinstalled latest/greatest POP Peeper. Cloned a profile from the working PC (too many email acc't variables to re-enter all manually). No change. Same behavior.

- Completely removed ALL antivirus/malware apps from problem PC using their 'clean' tools & reinstalled NIC/network drivers/stack. With nothing interfering w/ the network stack, many reboots, etc... no change. Same behavior.

- Reverted to an earlier version of Pop Peeper... 5.3, I believe... no change. Same behavior.

Having exhausted all the usual remedies, I find my self here. I can provide any additional info you require upon request.

The problem PC is my primary machine & I'd REALLY like to restore things to their previously working state. Hope you can offer a solution?

TIA
Last edited by li'loleme on Mon Apr 12, 2021 3:19 pm, edited 1 time in total.
li'loleme
Posts: 5
Joined: Mon Apr 12, 2021 12:35 pm

Re: ISP IMAP acc't(s) send mail problem

Post by li'loleme »

Well, I'll be buggered... just took the time removing the NIC/drivers again & upon reboot, I can send email. Now to reinstall my protection...

Thanks for the assistance I'm certain you would have provided!
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Jeff
Admin / Developer
Posts: 9227
Joined: Sat Sep 08, 2001 9:46 pm

Re: ISP IMAP acc't(s) send mail problem

Post by Jeff »

- Called ISP & verified NO blocks on their end. Jumped thru their "hoops"... send via webmail, etc... passed w/ flying colors. "NOT our problem."
Ugh. Do they think POP Peeper was pulling that error description out of its mail slot? At the very least, they should have been able to help you and tell you why it was happening. What they really mean is, "not worth OUR time."

However, this is telling:
Failed to Verify after EHLO

The EHLO is basically the very first thing that happens and the common thing to include is an identifier for your computer. This will generally be your network IP address, which is usually a meaningless local IP address, like 192.168.1.1 -- this is an IP address that probably millions of people have. So, more than likely, someone else has abused the system with the same internal IP address that you had, and perhaps your private IP address changed after you made changes. This also explains why your other computer had no problems, because they're going to have different private IP addresses.

POP Peeper used to use the name of your computer as an identifier. This is more in line with what the EHLO expects, but I also saw it as a PII issue, because it could include information that you may not feel comfortable sharing with every single person that you send email to. More importantly, it's information that you're probably not aware is being shared.

In POP Peeper, if you go to:
main menu: Tools / PPtweaker / Misc 2
you can specify the "computer name used in SMTP headers" -- put whatever you want in there.


There is one other possibility. I think that, as a general rule, the smtp server should effectively ignore the EHLO identification for the very reason I mentioned above -- asking a random computer to identify itself is rather pointless. That identification is more for server to server communication -- so your isp can identify itself to the receiving isp. The only thing that your ISP should concern itself with is your authentication, ie. your login/password. So make sure that you've set POP Peeper to actually log into your smtp server and isn't trying to use it anonymously:
1) Edit the account in POP Peeper
2) Select the 'Send Mail' page
3) Make sure "server requires authentication" is enabled

If you didn't already have that enabled, then that should fix the problem. If it's disabled, then that suggests your ISP allows anonymous email to be sent through their servers, which is generally frowned upon (and a good way for the servers to end up on DNSBL's, resulting in potential issues for the innocent users). It was actually pretty common back in the early days of POP Peeper, but that was almost 20 years ago...
li'loleme
Posts: 5
Joined: Mon Apr 12, 2021 12:35 pm

Re: ISP IMAP acc't(s) send mail problem [solved]

Post by li'loleme »

Thanks for your response, Jeff. Please note:

- "Cloned a profile from the working PC (too many email acc't variables to re-enter all manually). No change. Same behavior." Identical POP Peeper cfgs... set to use acc't credentials. Don't think anyone allows anon SMTP access anymore in this "age of SPAM"?

- Both PCs on same network, behind router, & err msg references external IP. Neither internal (static DHCP reservation)/external IP on affected PC had changed except for 'router MAC clone' experiment. With a new external IP. 1 PC still worked & 1 still failed with new external IP in the err msg. To be fair to ISP tech support (and it pains me to say it), this would bolster the "NOT our problem" determination.

- The "computer name used in SMTP headers" was/remains checked on both PCs, but field is blank. Problem? Don't recall having ever set this.

- The affected PC experienced no other network related issues beyond the failed EHLO handshake for all ISP IMAP cfgs (gmail IMAP cfgs were fine). It's a media PC, accessing multiple NAS targets, internet streaming sources, etc. Maybe it munged the EHLO announcement?

Only one symptom to indicate any network problem, at all & only completely nuking the NIC/drivers (2x) fixed the issue. No expert on email protocols, per se, but have been doing fault isolation for decades & I'm (old/) stumped. Fortunately, problem solved.

Thanks again for your feedback (& POP Peeper, of course)!
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Jeff
Admin / Developer
Posts: 9227
Joined: Sat Sep 08, 2001 9:46 pm

Re: ISP IMAP acc't(s) send mail problem [solved]

Post by Jeff »

The IP address that PP was sending with the EHLO is owned by your isp, so the command wasn't malformed or anything. If your internal and external IP's didn't change, then perhaps there was something in the network packets that they didn't like and the error just came in the form of reporting the IP address.

But as long as it works. And if it does happen again, I'd suggest simply trying to change your computer name in PPtweaker and see if that fixes it.
li'loleme
Posts: 5
Joined: Mon Apr 12, 2021 12:35 pm

Re: ISP IMAP acc't(s) send mail problem [solved]

Post by li'loleme »

Does the fact that the option is checked, but the field is blank pose an issue? If the null field is passed by both, wouldn't the originating PC be, for want of a better term, indistinguishable?
User avatar
Jeff
Admin / Developer
Posts: 9227
Joined: Sat Sep 08, 2001 9:46 pm

Re: ISP IMAP acc't(s) send mail problem [solved]

Post by Jeff »

There is no checkbox for that option. And, presumably, the fact that the error specifically mentions "EHLO [ipaddr]" that it means that that is what was sent to the server. PP has fallback options if it doesn't get the IP address (ie. the computer name is next).
li'loleme
Posts: 5
Joined: Mon Apr 12, 2021 12:35 pm

Re: ISP IMAP acc't(s) send mail problem [solved]

Post by li'loleme »

Thanks for all the intel, Jeff. I'll leave you alone, now. :D

Stay healthy!
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