L2TP VPN Server only accepts one client at a time

Question

We have an ISA570 on Site 1 with the following Network Config:
192.168.100.XXX
255.255.255.0
192.168.100.254 (GW)
ISA570
ISP Modem in Bridge Mode
So let us call my location right now as site 2. Although the network setup does not matter, let me just state it.
192.168.101.XXX
255.255.255.0
192.168.101.254 (GW)
Cisco RV042
ISP Modem in Bridge Mode
L2TP Client Network Pool:
192.168.103.100 - 192.168.100.200
255.255.255.0
DNS1 192.168.100.254
=======================================================================================
So here comes the situation
Client  1 with IP address of 192.168.101.24 connects to Site 1 via L2TP. He  uses this VPN Tunnel for a desktop application which is hosted at site  1.
Client 2 with IP address of 192.168.101.17 connects  to Site 1 via L2TP but is unsuccessful. Screen1.jpg below shows the  Windows VPN Error.
Screen1.jpg
I can not post my configs as of now because the WAN1 of site 1 is very congested. For now I will post the guides which I followed.
http://www.cisco.com/en/US/docs/security/small_business_security/isa500/administration/guide/ISA500_VPN.html#wp1393916
http://www.cisco.com/en/US/docs/security/small_business_security/isa500/administration/guide/ISA500_VPN.html#wp1479596
What am I missing here?

Answer 1

Hi Dan,
The site-to-site VPN tunnel should still work with those settings.  For the IPSec VPN Client, we have the Cisco VPN Client that should work.  There should be a copy of it on the CD that came with the ISA500. 
Here is a link that has information on setting up the Remote Access VPN on the ISA500:
http://www.cisco.com/en/US/docs/security/small_business_security/isa500/technical_reference/vpn/Configuring_VPN_with_Cisco_ISA500_Series_Security_Appliances.pdf
The section 'Configuration Examples of EzVPN, SSLVPN and Site-to-Site Between Cisco ISA500 Appliances' has an example at the beginning.
Let me know if that helps.
Thanks,
Brandon