Azure AD SAML login halts at blank screen after authenticating

[from_afar]

Testing Azure AD SAML auth with our Meraki Secure Client and I have configured Azure as well as the test Meraki MX68 according to thist guide https://documentation.meraki.com/MX/Client_VPN/AnyConnect_on_the_MX_Appliance/AnyConnect_Azure_AD_SA.... We are using a custom FQDN which is a CNAME pointing to our <host>.dynamic-m.com domain. I did this so I could purchase a SSL certificate which I have done and uploaded to Meraki admin. When testing the setup in Azure, it passes with no errors or issues. Same for when I try to log in to the VPN with Secure Client. The problem is that after authenticating to Azure in AnyConnect Web Helper windows, I get a "Stay signed in" window with "do not show again" Checkbox and Yes/No buttons. No matter what I click or choose here, the auth window just goes blank and nothing else happens for about 3-5 minutes. Eventually, it will time out with a "This page is not working right now" error. In my research, I found one other user with a similar issue and they were able to work around the problem by hitting F5. Unfortunately, that doesn't work for me--I just get a "resend information..."warning and back to the blank white page. 

In my Azure SAML config, the Entity ID is set to https://vpn.example.com/saml/sp/metadata/SAML the Reply URL https://vpn.example.com/saml/sp/acs 

I have Secure Client Ui 5.1.1.42, AnyConnect 5.1.1.42; MX devices auto-update over the weekends so should be running latest stable.

I tried clearing out all Cisco Cookies from Edge and Chrome. I tried changing default Browser to Chrome. Other forums say the Cisco Web Helper should be using WebView2 Runtime anyway which is installed. 

Any ideas what could be causing this? Or where I should look for hints as to what is going on?

[PhilipDAth]

> I get a "Stay signed in" window with "do not show again"

Can you post a screenshot of this window please.  I cant think of what it could be.

[from_afar]

Sure thing, it looks just like this except with our company branding etc.

Standard part of the Microsoft 365/Azure auth workflow.

[Gary_Geihsler1]

Is this question specific to the product Secure Connect or are you trying to create VPN to the MX itself? This community is specific to Secure Connect so if the question is for client VPN to the MX you would have better results in the MX Community. 

[from_afar · Accepted solution]

Not sure how/why, but the next day it started working fine. The blank page goes away and I get the familiar "You are connected" message and the VPN works. No idea what caused or fixed the issue...