Invalid Line

[jolouis]

(10-24-2017 01:12 PM)Jen Wrote:  Good afternoon,

We have 2 W52P's at our site. We frequently have the message 'invalid line' come up on the phone and we are unable to make or receive calls. A reboot of the router appears to resolve the problem but we need to determine why it is happening in the first place so we can stop it happening in future as it wastes a lot of our time.

Can you please advise?

many thanks

If you have to reboot the router to resolve the problem, then logic would say problem is not with the W52s but with the router blocking something. As pointed out, sounds like the registration is failing, most likely because the router is blocking packets for some reason.

Try checking to make sure that there is no "SIP ALG" enabled on your router. Failing that, try replacing the router with a different make/brand and see if that helps.