Sign in to Azure AD behind a proxy server

Question

Hi there,

for some tests I have to sign in to AzureAD from a machine that is located behind a proxy server and therefore can only access the internet through the proxy server. I got the AzureAD join working after I had configured the proxy server for the system context using the command

netsh winhttp set proxy

But unfortunately I was unable to sign in to the system with my AzureAD account. The firewall logfiles show that the system tries to bypass the proxyserver. These attempts fail as expected. I also read that one should configure the proxy settings in the file C:\Windows\Microsoft.NET\Framework64\v4.0.30319\Config\machine.config according to the following pattern

<system.net>
<defaultProxy enabled="true" useDefaultCredentials="true">
<proxy usesystemdefault="true" proxyaddress="http://{FQDN Proxy}: Proxyport}" bypassonlocal="true"/>
</defaultProxy>
</system.net>

Unfortunately this solution in combination with a reboot after changing the file doesn't work either.

What else can I try?

Thanks in advance.