Billion UK Forum

Hi, just installed an 8900-AC2400 and from my home PC everything works really well, in fact performance speeds are exceeding anything I've been able to achieve up till now, so very happy. I'll on a TalkTalk Fibre connection (VDSL).

My issue is that with the TalkTalk provided router I can use my work PC to connect to company VPN (IPSec based, Avaya client on locked down Windows 7 PC). With the 8900, on the work PC I can connect to the internet, so I'm getting a wireless connection and have confirmed that the internet is accessible, but VPN keeps failing to authenticate, with message 'Unable to reach server'.

I've tried the various suggestions for this type of situation, modifying the MTU down to 1400 from 1500 and ensuring that NAT Transversal is on etc, but no joy. Anyone else having the same issue or better still been able to determine a fix?

I'm not a network specialist, but would appreciate any thoughts on a way forward as I don't really want to return to the crappy TalkTalk router performance.

isablend wrote:Hi, just installed an 8900-AC2400 and from my home PC everything works really well, in fact performance speeds are exceeding anything I've been able to achieve up till now, so very happy. I'll on a TalkTalk Fibre connection (VDSL).

My issue is that with the TalkTalk provided router I can use my work PC to connect to company VPN (IPSec based, Avaya client on locked down Windows 7 PC). With the 8900, on the work PC I can connect to the internet, so I'm getting a wireless connection and have confirmed that the internet is accessible, but VPN keeps failing to authenticate, with message 'Unable to reach server'.

I've tried the various suggestions for this type of situation, modifying the MTU down to 1400 from 1500 and ensuring that NAT Transversal is on etc, but no joy. Anyone else having the same issue or better still been able to determine a fix?

I'm not a network specialist, but would appreciate any thoughts on a way forward as I don't really want to return to the crappy TalkTalk router performance.

Try the following

1. Login to router
2. Click on 'Configuration >> NAT >> ALG'
3. Disable the 'IPSec' option
4. Click on 'Apply'
5. Try your VPN connection again

I cant profess to understanding why that suggestion worked, but it did. Now a very happy bunny as it all now works. Many thanks.