VPN / L2TP problems

[Ray]

I have set up a Windows 2000 RAS servers to handle PPTP
and L2TP connections. The PPTP connections seem to work
fine, but I am having a lot of problems with L2TP. L2TP
does not seem to be consistant, some times it works, some
time it doesn't. Now that I have IPSec configured on the
RAS server it seems like I have no problem creating a
IPSec connection between the client (also win2k) and the
server, it seems to be with the certificates that is
flaky. I have set up certificate server on windows 2000,
and several times I get an error trying to get a
certificate for the client. It says it can't find the
certificate server. Then the next day it might work.
Also I have l2tp clients that work one day and the next
they don't. Does anyone know what could cause this?

 

[Ray]

I think i have a patern to what is going on but I still
can't figure it out. One problems is still getting a
certificate threw mmc and certificate manager. Sometimes
it finds the certificate server, and some times it
doesn't. But the pattern I think I am finding with the
l2tp is if I try an l2tp connection it fials and I need to
reboot. Once I reboot if I do a IPSec PPTP connection
first, then disconnect and change it to a L2TP connection
it connects fine. I have been able to duplicate this
several times. If I try L2TP first no matter what I do,
I can't connect even with pptp without rebooting. But
once I reboot and try PPtp first, then L2TP it works. Any
help anyone could give me would be greatly appreciated.