Unable to access Web GUI

[B-C]

Unable to access any yealink devices from browser...
any browser..
Loads login page but login doesn't do anything -
No Error - Nothing
Haven't attempted to manage a phone via GUI in some time (maybe 6-7 months)
possibly since upgrading to Windows 10.

Windows 10
vipre AV Endpoint security -
also disabled active protection temporarily to see if that helped - No change
disabled AV 100% No change

loads login page fine
entering credentials does not work.

Attempted Chrome
Disabled Adblock Plus - no change
Disabled HTTPS Everywhere - No change

firefox
Disabled all addon's same issue

Edge - No addons
Same issue

IE - No addons
Same issue

attempted mobile android (chrome) as well just to test
same exact issue.

able to load interface so it is definitely working - just not sure what is causing the issue. all our T42G/T46G devices.

other devices like Grandstream GXP2140s working fine.
with addon's enabled

also - Why is forum not https? really LetsEncrypt isn't that difficult - I mean Free?!? - pretty easy to setup!

-
1 phone on newer firmware:
29.80.0.70 T42G - is working normally - all addons' enabled
checking cache and flushing to see if that helps

Nope - No change