topic Re: IP address blocked by Microsoft? in Everything else

IP address blocked by Microsoft?

quicksilver1 — Thu, 18 Sep 2025 13:37:14 GMT

First post here as this is the first issue I've had in many years with Plusnet.

For months now I have been unable to sign in using a password to any Microsoft Outlook email account on any device on my home network. I always get a plain text error string saying "Please try a different device or network" or sometimes different text along the same lines. I've got nowhere trying to troubleshoot with Microsoft but I discovered I can sign in okay on my phone via mobile data. That suggests sign-in requests from my public Plusnet IP are being blocked by Microsoft for some reason.

Is this plausible and what can be done to fix it?

Re: IP address blocked by Microsoft?

Baldrick1 — Thu, 18 Sep 2025 14:24:05 GMT

Moderator's note:
Thread moved from Everything Else to Email

Re: IP address blocked by Microsoft?

Townman — Thu, 18 Sep 2025 15:19:42 GMT

Is this related to a Plusnet email service or is the end point for your email client @outlook.com / @hotmail.com / @live.co.uk etc?

Configuring access to Outlook email accounts can be a pain in the neck these days - it is not your password you need but a one-time app password - it is all part of their "extra secure" access controls. I call it just making life harder for those who do not understand technology!

You need to google this issue and follow Microsoft support information.

Re: IP address blocked by Microsoft?

quicksilver1 — Thu, 18 Sep 2025 15:22:12 GMT

It happens when logging in to Microsoft email (@hotmail.co.uk or @hotmail.com) via the webpage login.live.com. I select the option to log in with a password, enter the correct password and on Tesco mobile it signs me in normally but on Plusnet wi-fi I always get the error message.

Re: IP address blocked by Microsoft?

Townman — Thu, 18 Sep 2025 15:27:09 GMT

So to clarify, it is a mobile device, if connected to the mobile network, it works, if connecting via Wi-Fi over a Plusnet connection login fails. Aside from login failing everything else works correctly over Wi-Fi?

You might have an abused dynamic IP address. Try switching the router off for 2 hours, then see if you get a different IP address and a different experience.

Re: IP address blocked by Microsoft?

Baldrick1 — Thu, 18 Sep 2025 15:30:36 GMT

Moderator's note: After further clarifi\tion thread returned to Everything Else.

Re: IP address blocked by Microsoft?

quicksilver1 — Thu, 18 Sep 2025 15:36:52 GMT

Close but not quite. My phone can log in successfully via mobile data but every device connected to the Plusnet network including multiple laptops and the same phone throws the error message. Everything else involving the network works fine.

An abused IP is certainly a possibility. I'll try turning off the router tonight and see if picking up a fresh IP makes any difference.

Re: IP address blocked by Microsoft?

quicksilver1 — Fri, 19 Sep 2025 08:27:13 GMT

Quick update. I haven't forgotten to power off the router, just delayed it. It occurred to me that changing IP might cause all Outlook accounts to log out automatically. I couldn't find a definitive answer and didn't want to take the risk of being totally locked out if the IP change didn't fix it and other sign in methods also failed, so I tested a few things this morning.

Signing in with the password on a laptop using the phone as a hotspot works, which supports the IP block theory. I'll power down the router tonight and see if a new IP fixes it.

Re: IP address blocked by Microsoft?

quicksilver1 — Sat, 20 Sep 2025 09:22:09 GMT

Success! Powered up the router this morning with a new IP and sign-ins are working as they should.

Thanks to @Townman for pointing me in the right direction. After hours of hitting dead ends with Microsoft's useless automated support, a short chat with a real person who knows stuff about networking was all I needed to fix it. You've done more to help resolve an issue that wasn't even Plusnet's fault than Microsoft whose fault it is.

My only concern is the blocked IP getting used again and causing this same problem for someone else further down the line. Is there any way for Plusnet to get it unblocked or taken out of use?

Re: IP address blocked by Microsoft?

Townman — Mon, 22 Sep 2025 15:10:01 GMT

@quicksilver1

Thank you for your words of appreciation.

I might though argue that this is neither specifically Plusnet's or Microsoft's issue, in the absence of knowledge of why the address was black listed. There are multitude of reasons as to why an address gets black listed, some are legitimate whilst others are false positives.

There are thought cases where users do abuse the service both intentionally and unwittingly. One does wonder if Plusnet could be swifter to detect such and close down the abuse before the IP address get blacklisted.

You ae correct to have a care about some other user acquiring the blacklisted IP address - generally these clear of their own accord after the passage of time. Some blacklists do though require intervention.