Had a 2-hour nightmare getting switched around with no one having a clue. Both my laptop via hotspot and cell phone have IP that is registered to T-mobile blocked in Spamhaus, McAfee and lots of other spam listing sites. Obviously not from me but lots of folks must use these shared IP's.
I am a Metro PCS customer but using the T-mobile network roaming in Toronto Canada via Bell (and others). I have their Mexico/Canada package. The IP that gets assigned per whatismyip is T-mobile. Data, incoming e-mail and phones work fine with about 3 times the speed of my hotel's wi-fi. I have my own STMP client so I see the server response directly otherwise would not know mail is being blocked. One IP is 126.96.36.199 on the laptop and similar on cellphone just different 3rd and 4th numbers but again listed in Spamhaus etc.
The IP registration is:
IP Address Country Region City
188.8.131.52 United States Texas Dallas
ISP Organization Latitude Longitude
T-Mobile USA Inc. 2.783058166504 -96.806671142578
I can solve by whenever I want to send e-mails by switching to hotel wi-fi whose IP isn't blocked. I tried rebooted both cell and laptop and reestablished hot spot thinking there would get me a roaming IP that would change. Nope, still have the same blocked IPs. Would be nice to not have to switch just to send e-mail!
I once had a cox IP locked this was in Phoenix and easy reached tech support who understood the problem, tried to trace who using the IP might have been sending spam, contacted who was blocking and gave me a new static IP to bypass it.
This is a long description of my about 2+ hour dead end journey with tech support by phone.
Since it's a T-mobile IP I call T-mobile tech support. They don't really understand the issue but transfer me to another Tech support line, but after about a 30 minutes on hold listening to music, they are totally confused but its just customer support like teaching you how to set up an account etc. They transfer me they say to Tech support for Metro PCS. Another about 30 minutes to connect to a live person after hitting 0 for operator about a dozen time to get out of automation that asks if I want to set up an account, make a payment etc with no tech support option. I again explain the whole situation that it is a T-mobile IP that is blocked.. its just customer support for Metro PCS that has no clue and tries to explain how I should set up my phone which has no relevance to the problem. They give up and have no clue and again try and connect me to tech support instead of customer service (each time I am told they ARE connecting me to tech support but keep winding up with just customer support).
Another long wait and get out of the "do you wish to make a payment select 1" que I get a gal who doesn't have an accent that is easy to understand. Very friendly... kind of gets the real issue but has to check with her supervisor. Then comes back and tells me the IP is assigned to the phone and need to reset up the entire account (totally wrong my phone has a different IP). Then back to supervisor while I am on hold back and forth a few times with answers like since no I am not using something like Hotmail I need to contact my domain provider ... I explain I know that isn't the issue since the IP is owned by T-mobile not my domain host. Then I have to explain that I have an e-mail client that is not web based. Then she says there is no way they can change my IP. I ask then who can or who can get it unblocked. No clue.
While on hold I also send a test e-mail using outlook but since it is using usual mail account and not my SMTP client it never tells me the problem. But I never get the test e-mail reaching me (use different e-mail addresses). Again the problem is the T-mobile IP that is blocked.
After giving up reaching anyone with any answer, I check directly with Spamhause where you can look up blocks etc. Yes the IP from T-mobile is blocked but not only by PBL but scads of other spam serves including McAfee and zillions I've never heard of.
Then I look up the IP the phone is using (vs laptop via hotspot). Guess what? That is also a blocked T-mobile IP with slightly different 3rd and 4th tier numbers - 184.108.40.206.
Again data, fast speeds, incoming e-mail and phones all work find, only outgoing e-mail is blocked since someone on the IP was spamming or sending a virus. In one of the reports it says was used for some zero something virus.
OK, I give up. I just have to switch to hotel wi-fi to send e-mail. I thought someone at T-mobile should know since anyone using these blocked IPs will not be able to send e-mail and probably not know it is blocked since the e-mail client shows it has been "sent". It is only blocked at the SMTP level. I have no idea how T-mobile IPs are assigned or how many the have.