Problem with connecting to Point-to-Site VPN the message received was unexpected ot badly formatted

Hello AUser

Looking at the issue you described it occurs me the VPN client may not be able to access the CDP (certificate revocation distribution point) location (LDAP, CIFS, HTTP) as specified in the CDP extension of the client certificate. Therefore when the client is validating the certificate e.g. building the certificate chain (which you said it can do), then checking the integrity of the chain it will fail this second element (sometimes performed together) if it cannot reach any of the locations as specified in the CDP (or the Automotive Information Access extension if using OCSP for revocation checking). Therefore bottom line if using a certificate issued by a CA, then on the computer with the VPN client installed, use the following command to verify access to CRL  

certutil -f  -urlfetch –verify  If all the locations in the CDP (LDAP, CIFS, HTTP) fails then resolve this first

Please let me know if this fixes your problem,

Ernest Brant