connection to vpn fails (sonicwall client through linksys router)

I'm trying to connect to my office using sonic client and consistently failing. Actually sonicwall client informs me that connection to network is established, but when I tried to access one of the computers remotely using remote desktop it fails.

Here is a sonicwall log:

2009/09/24 12:54:58:109 Information <local host> Renewing IP address for the virtual interface (00-60-73-ED-F9-E6).
2009/09/24 12:54:58:187 Warning     <local host> Failed to renew the IP address for the virtual interface.
2009/09/24 12:55:03:359 Information <local host> The IP address for the virtual interface has changed to 192.168.0.xxx.
2009/09/24 12:55:03:421 Information <local host> The system ARP cache has been flushed.
2009/09/24 12:55:03:484 Information {ipaddress} NetWkstaUserGetInfo returned: user: user, logon domain: mymachine, logon server: mymachine
2009/09/24 12:55:05:750 Information {ipaddress}  NetGetDCName failed: Could not find domain controller for this domain.
2009/09/24 12:55:05:750 Information {ipaddress}  calling NetUserGetInfo: Server: \\mymachine, User: user, level: 3
2009/09/24 12:55:05:750 Information {ipaddress}  NetUserGetInfo returned: home dir: , remote dir: , logon script:

I suspect that my router is not allowing connections, router I'm using is linksys WRT54G v8.2

Any help would be very much appreciated.

From serverfault krul

• I have seen this same problem with Checkpoint's VPN. The issue is basically an overlapping IP scheme on your home network with that of your company. So if your office uses 192.168.1.1 in one of the networks and your home uses the same scheme then the problem surfaces. Try changing your home network to something else and see if that fixes it. An alternative is to check the settings of the VPN client, Checkpoint has an "office mode" that alleviates this problem.

  krul : My router uses 192.168.1.1 ip address. What might be the side effect of changing this ip on router?

  EasyEcho : You would need to reboot all machines on the network that have dynamic ip assignments (dhcp) so they get one with the new scheme and any static ips you would need to change manually. Other than that there should be no issues.

  EasyEcho : Also it only matters if 192.168.1.1 is also in use at your employer. Otherwise don't waste your time changing the IP. The issue could also be that Remote Desktop isn't allowed through the VPN tunnel, again checkpoint requires explicit rules for VPN users and so we have a rule to allow Remote Desktop from VPN to our internal network.

  krul : Thank you very much for your suggestions and explanations, I changed router ip and tried again but it didn't help. I will inform you guys once/if I resolve this issue.
  From EasyEcho

• Here is update on my connection problem. I tried to connect yesterday (in order to document connectivity issue) expecting error. On my surprise I was able to connect. I changed nothing on my router and on my computer since last failed attempt. I noticed that ip given was different from the one when I was failing to connect. That leads me to believe that the problem was indeed IP overlapping as EasyEcho pointed out. That is the reason I'm accepting his response as answer. Thanks again to everybody that tried to help me.

  From krul