Solved 3CX Windows Client Connectivity Issues

[watsee]

Hi there,

We use the 3CX Windows Client across all the desktops, laptops and tablets we use at the IT firm I work at. Currently one of our guys is having some strange issues when trying to use the 3CX Client on his Microsoft Surface Pro 4 (Windows 10).

When he tries to use 3CX on the Office Wifi, his 3CX will not connect. However if he uses another Wifi network at home or elsewhere - it loads fine. We have tested with an ethernet cable and this worked without issue too. However, using an ethernet cable full time isn't an option.

Myself and 2 colleagues also have Microsoft Surface Pro 4's on Windows 10, all up to date (with creators update installed also) and we have zero issues with the 3CX system on the office Wifi.

It is not a firewall issue on his Surface, as our firewall is managed internally & 3rd party firewalls are disabled.

Its a strange issue and we're all a little confused as to why this might happen.

Any ideas? Any help is very much appreciated.

 

[leejor]

Does the 3CX Activity log show a registration attempt, with a possible rejection for some reason, perhaps the IP is blacklisted?
You would probably be picking up a different IP when using a cable.

 

[watsee]

That's exactly what it was! His IP whilst on Wifi had been blacklisted for 'too many failed authentication attempts'. Removed the IP from the blacklist on the 3CX Management Console and presto! It worked.

This has scored me massive points at work, much appreciated!

 

[leejor]

I had some ATA's that would randomly be blacklisted every once once a while for no reason. i ended up white-listing the entire local LAN as it doesn't create a security issue, in my case.

 

[watsee]

Yeah I noticed a few blacklisted IPs across our network range, for whatever reason. Just whitelisted the entire range to prevent this from happening again. Thanks once again.