Comcast email doesn't load on iPhones when connected to network - works on PCs with same settings

AWDOnly

Hi all - hoping you can help me solve a bit of a mystery that has me pulling my hair out. the scenario is as follows:

I have 3 different email services, this question ONLY applies to comcast.net emails. Other 2 work fine.
Comcast email loads fine on multiple PCs in Windows and Linux on the local network (pfsense) when they are connected via ethernet or wi-fi.
Comcast email account settings (servers / ports / security, etc.) same on our iPhones as on PCs.
Comcast email on iPhones loads fine when connected to internet via cellular provider (5G).
Comcast email doesn't work when connected to home network (pfsense - same network as PCs).
IPhones connected to pfsense network attempt to get comcast email, but it times out then gives this message: "Cannot Get Mail - Comcast is currently unavailable."

Anyone have any idea why same Comcast email accounts with same settings on PCs work fine on pfsense network, but iPhones with same settings do not (although those settings work fine to collect email when iPhones connected to internet via 5G?

stephenw10

Are you doing any DNS filtering or redirecting in pfSense?

AWDOnly

@stephenw10, I am not.

stephenw10

Are the iphones trying to use IPv6 perhaps?

Gertjan

@AWDOnly said in Comcast email doesn't load on iPhones when connected to network - works on PCs with same settings:

Comcast email doesn't work when connected to home network (pfsense - same network as PCs)

This includes / excludes PC ? Other devices ? iPhones only ?

@AWDOnly said in Comcast email doesn't load on iPhones when connected to network - works on PCs with same settings:

IPhones connected to pfsense network attempt to get comcast email, but it times out then gives this message: "Cannot Get Mail - Comcast is currently unavailable."

Only iphones.

As you might suspect, there is no iPhone detection in pfSense.
More probably, this setting is set (green) :

so the MAC will be a random MAC, pfSEnse really can't know it deals with an iThing.

IMHO, Comcast is a very big ISP. I presume some of their clients use pfSense and have iPhones (iPads).
Comcast - iPhones - pfSense => mail doesn't work ... that would not go silent.

So, what I think : re check your iphone email pop and/or imap settings.
With an iPhone (iOS), you can not validate mail settings if something is wrong == if the service can't be accessed = a succeeded login.

Check the URL.
Most probably : select TLS.
So the port for POP it will be 995, but check with comcat what their TLS pop port is.
IMAP will be 993, but check with comcat what their TLS pop port is.
Same thing for smtp btw. 587 ? 445 ?

.

AWDOnly

@stephenw10, I don't think so. iPhones work fine on the network for internet access and the other 2 email accounts, and I believe I have IPv6 disabled in pfsense.

AWDOnly

@Gertjan, the iphones are on the same pfsense network as the PCs that work. I don't have any android phones to try so my experience here is limited to the iPhone. I did try turning off the private wi-fi address as you suggested. No change - I still can't access comcast email when connected to home network but can access internet and other 2 emails work fine. The email is set up correctly as well since it works fine when disconnected from home network - connecting through 5G. Thanks for the suggestions.

stephenw10

A partially configured v6 address will be used by some OSs and not others. So if that one mail address resolves to both v4 and v6 addresses that may explain the difference.

AWDOnly

@stephenw10 - Thanks for your thoughts. I'll try to turn v6 back on when I get back home this evening and see if that resolves the issue.

stephenw10

It might not be that but we have seen that be an issue that can present as client types behaving differently. So worth checking.

AWDOnly

Hi all - iPhones do collect emails on other wi-fi networks. I've also tried turning off "Private Wi-Fi Address" and "Limit IP Adress Tracking" on the iPhone settings. Neither made a difference.

stephenw10

Ultimately try running a pcap on pfSense for the IP of the phone then try to check the email and see what it's sending.

AWDOnly

@AWDOnly said in Comcast email doesn't load on iPhones when connected to network - works on PCs with same settings:

@stephenw10 - Thanks for your thoughts. I'll try to turn v6 back on when I get back home this evening and see if that resolves the issue.

Turning IPv6 on made no difference.

AWDOnly

@stephenw10 said in Comcast email doesn't load on iPhones when connected to network - works on PCs with same settings:

Ultimately try running a pcap on pfSense for the IP of the phone then try to check the email and see what it's sending.

I'll try - I haven't actually used pcap previously so will have to figure it out.