Just some notes:
http://support.microsoft.com/kb/926182
I order to run  an IPSEC/NAT-T type VPN you need to insert the following registry keys on the client : 
XP SP2: 
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\IPsec] 
 "AssumeUDPEncapsulationContextOnSendRule"=dword:00000002” 
Vista: 
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\PolicyAgent] 
"AssumeUDPEncapsulationContextOnSendRule"=dword:00000002” 
Now... I'm not quite sure that these alone will help you get connected. 
Make sure that since you are connecting from a non-domain member that you certificate is properly installed. 
Import the Administrator-Cert to both 
Local Machine: "Personal" & "Trusted Root Certification Authorities" 
This in combination with the above registry-hack should do it. 
BTW: The one for SP 2 is documented in: http://support.microsoft.com/default.aspx?kbid=885407 
The one for Vista is not... but it works   
 
[TX Geir Johansen, isaserver.org]
OK, here is a way to do it (but it is not an easy 
solution). 
1) You need to use certmgr.msc on the Vista Client 
2) You need to generate Custom Request in the console 
(see Create a Custom Certificate Request in the Help 
file). 
3) Best to add Custom subject information (be sure to 
include an Alternate Name that includes the User 
Principal Name 
4) Save the file to a PKCS#10 request 
Create a custom v2 certificate template that allows the 
Subject to be created in the Request. Base it on the 
template you want to use (for the love of G*D, do not 
use User <G>) Ensure that the template is available at 
the CA you are using. Assume it is named VistaUser 
You now use the Certsrv Web page to submit the request 
1) Connect to https://CAName/certsrv 
2) Provide credentials from the domain 
3) Choose Request a Certificate 
4) CHoose Advanced Certificate Request 
5) Choose Submit a certificate request by using a base-   
64-encoded CMC or PKCS #10 file, or submit a renewal 
request by using a base-64-encoded PKCS #7 file. 
6) Paste the contents of the file created in the first 
procedure into the Saved Request box 
7) Choose the VistaUser template in the Certificate 
Template sectino 
8) Click Submit 
9) Save the issued certificate to a PKCS#7 file (all 
certs in the chain) 
Go back to the Vista box 
1) Import the PKCS#7 file 
2) Put all certs in the Personal store (for now) 
3) Once the import is complete, move the CA certificates 
into the appropriate stores (root in the root, all other 
CAs in the intermediate store 
4) Use the certificate 
Brian 
P.S. Please do not ask for more detailed steps <G> 
In article <D85CB163-D832-4D40-B009-B5A28A685BF0 
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