[squid-users] microsoft edge and proxy auth not working

[Rietzler, Markus (RZF, Aufg 324 / <RIETZLER_SOFTWARE>)]

we have some windows 10 clients using microsoft edge browser.
access to internet is only allowed for authenticated users. we are using samba/winbind auth 

auth_param ntlm program /usr/bin/ntlm_auth --helper-protocol=squid-2.5-ntlmssp
auth_param ntlm children 64 startup=24 idle=12
auth_param ntlm keep_alive on
acl auth_user proxy_auth REQUIRED

on windows 10 clients with IE11 it is working (with ntlm automatic auth) on the same machine, with Microsoft edge I get TCP_Denied/407 message. seems I only get one single TCP_DENIED/407 line in accesslog and an auth dialog pops up. I have disabled basic auth via ntlm.
shouldn't there be 3 lines for proxy auth? with IE11 I see those three lines (2x TCP_DENIED/407 and 1x TCP_MISS/200), no popup at all.

winbind/samba itself seems to work, as I can do an user auth against apache with winbind/samba - even over some squid proxies with connection-auth allowed. but not for proxy-auth.
is there any option in squid.conf which prevents Edge to do a successful auth?


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Markus Rietzler