Azure Portal cannot be accessed - The Request is blocked

Question

Hi,

actually we are not able to access portal.azure.com from our corporate Network. Outside our corporate Network it is possible to access, but not within.

Our Firewall is not blocking, Cookies are empty, same with different browser, we have no proxy. Other Apps can be accessed like M365, EAC, MS Teams etc., only office.com & portal.azure.com are not accessable.

Has anybody an idea why?

Answer 1

Hi @ADConnect ,

If you are using a VPN and can disable it, I would try turning it off to see if you are still blocked. I would also recommend checking your browser traces to see if you there are any error messages to indicate what the problem might be.

Your firewall needs to be configured to allow the Azure Portal URLs as documented here, so I would recommend verifying that the URLs have been added to your allow list. If that access is already enabled, there could be a separate issue.

Another possibility is that there are Conditional Access policies in place on the tenant that may be blocking access based on some condition that would only apply to the sign-ins from the corporate network. https://docs.microsoft.com/en-us/azure/active-directory/conditional-access/troubleshoot-conditional-access

Since you mentioned that this issue is happening both in the Azure Portal and in the Office portal site, the issue might be related to the backend of your tenant and may require deeper troubleshooting. If you have already tried all of the steps mentioned, feel free to send me an email at AzCommunity@microsoft.com ("Attn: Marilee Turscak") and include your Subscription ID and a link to this thread, and I will open a support case to address your issue.

If the information helped you, please Accept the answer. This will help us as well as others in the community who may be researching similar concerns.

Answer 2

Hi Marilee,

thx for your response. I have tried all the steps before and this brought no solution.

At least it was the external IP, which was listet by MS and there they blocked the request.

We had an internal Server, which has generated a large number of request which led to a bad reputation and this resulted in requests from us to MS being blocked.

Thx for your support :-)

Best from Germany

sueleyman

Answer 3

Same issue in Chrome browser: Azure portal could be accessed through another browser on the same machine or even through Incognito mode in Chrome. Looks like there is some cached data that blocks the access. Can someone advise please?

Answer 4

I think the problem is the wrong configuration of the DNS.

I have tried to changed the DNS to the following:

1.1.1.1

1.1.2.2 or 1.0.0.1

You have to change it in your IP config and on the router config.

It works for me, so I hope it will work for every body.

Hope that helps.