Solved

cannot telnet to port 110

Posted on 2010-09-07
8
662 Views
Last Modified: 2012-08-13
Hi. today we started having problems emailing from our office. We all use pop email.  We were getting an error message in outlook saying it could not connect to the incoming mail server. I contacted our mail host who said it was an issue with our isp who did not have an rdns entry for our ip address. I contacted our isp who said they do not setup rdns on dynamic addresses. So I am confused. For a test I attempted to telnet to our mail host and could not at the office but could at home (different isp). I can also telnet on port 110 to several other mail server without a problem from the office. Can anyone shed some light on this for me? Or perhaps give me an idea what other tests I can do to try and confirm where the problem really lies?

0
Comment
Question by:linknetworks
  • 4
  • 3
8 Comments
 
LVL 82

Accepted Solution

by:
Dave Baldwin earned 500 total points
Comment Utility
Go to Shields Up! on grc.com where you can check to see if port 110 is being blocked. https://www.grc.com/x/ne.dll?bh0bkyd2   If it says 'closed' then your ISP or firewall is not blocking it.  If it says 'stealth' then something is blocking it.
0
 
LVL 3

Expert Comment

by:RedITAus
Comment Utility
Are you unable to telnet to that server both by IP and FQDN?
0
 

Author Comment

by:linknetworks
Comment Utility
I went to the shields up site and ran the test on all service ports which showed all ports were "stealth".

I am unable to telnet by both ip and fqdn.
0
 
LVL 82

Expert Comment

by:Dave Baldwin
Comment Utility
That's may not be good.  What is working at work?  Do you have a router with firewall?  Do you know anyone else with this ISP that can run the Shields Up test also so you can compare results?
0
Threat Intelligence Starter Resources

Integrating threat intelligence can be challenging, and not all companies are ready. These resources can help you build awareness and prepare for defense.

 

Author Comment

by:linknetworks
Comment Utility
I ran the shields up test on another client with the same isp. The results were different, with a number of ports including 110 not showing stealth.
0
 
LVL 82

Expert Comment

by:Dave Baldwin
Comment Utility
So your task now is to find out what is blocking your ports at work.  How are your computer configured?  Do you have a Windows server network or just a peer network?  What do you go thru to connect to the internet?  Is anything still working?
0
 

Author Comment

by:linknetworks
Comment Utility
Thanks Dave, things are working again. It was definitly the isp. I reset the adsl modem and router and recieved a different address which works on port port 110. I am recommending to the client to move to a different isp. I talked to two seperate techs at the isp yesterday who were no help whatsoever. You would think they could have at least suggested restarting the modem to get another address. I don't know maybe I should have thought of that.
0
 
LVL 82

Expert Comment

by:Dave Baldwin
Comment Utility
Glad you got it working.  In a lot of places, the people who answer the tech support line are just phone answerers with scripts and not much tech knowledge.  That makes it more of a do-it-yourself thing unless you can get it escalated.

ADSL modems that I have used and dealt with seem to be very susceptible to brownouts screwing up their operation without showing any errors.  So anytime your internet access seems to suddenly act differently, keep your modem in mind.  I would also ask your ISP if they offer a fixed IP option.  I have always had a fixed IP so I could use remote mail servers on all the web sites I maintain.  It used to be a requirement with my ISP.
0

Featured Post

How your wiki can always stay up-to-date

Quip doubles as a “living” wiki and a project management tool that evolves with your organization. As you finish projects in Quip, the work remains, easily accessible to all team members, new and old.
- Increase transparency
- Onboard new hires faster
- Access from mobile/offline

Join & Write a Comment

Suggested Solutions

Microsoft Outlook is not just an email client but it is full featured Personal Information Manager. But sometimes Outlook gets disconnected and you simply can’t access it. What steps can you perform before calling IT support? In this article we will…
Automapping, a wonderful feature with Exchange 2010 (SP2 onwards I believe), allows additional/Shared mailboxes that a user has access to be automatically mapped on Outlook client, simplifying the process by adding them while Outlook launches. Ho…
In this video we show how to create a Distribution Group in Exchange 2013. We show this process by using the Exchange Admin Center. Log into Exchange Admin Center.: First we need to log into the Exchange Admin Center. Navigate to the Recipients >>…
In this Micro Video tutorial you will learn the basics about Database Availability Groups and How to configure one using a live Exchange Server Environment. The video tutorial explains the basics of the Exchange server Database Availability grou…

743 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

8 Experts available now in Live!

Get 1:1 Help Now