Topic: OpenVPN issue on Windows Vista and Windows 7

[ddougan]

I have several clients with OpenVPN running quite successfully; however, I recently installed it on a new client's server running SME Server 7.4 + updates, where I have an odd problem. I can connect successfully and map drives with an -up.bat script from any number of XP systems; however, from a Vista 64-bit system at the client's satellite office and from my Win 7 test box I get a weird problem - the VPN connects successfully (I'm able to ping the server's tap interface), but when I try to map drives, I get a "System error 64 has occurred" message on the client. Initially, I was able to map drives, but a couple of days after installing the client software, the Vista user reported the System 64 error.

What makes it odder is that I can connect to OpenVPN on another client's server from the same Win 7 box and, although they do not display in Windows Explorer, the drive mapping script runs without error. In researching the differences between the two servers, I saw that OpenVPN on the new server was a later version (openvpn-2.0.9-1.el4.rf.i386.rpm, via Jesper's How-to). In trying to debug this, I have uninstalled the newer version (and lzo2) and installed the version from the other client's server (openvpn-2.0.2-1.2.el4.rf.i386.rpm). After restarting the daemon, I still had the error message.

The ovpn files are the same apart from the remote parameter; similarly, the server.conf files differ only with domain names (they happen to have the same IP addresses) but otherwise are per Jesper's packaging.

I'd appreciate any ideas anyone might have as to why this is not working.

Thanks,

Des

[Stefano]

I think this is a windows issue  but..

is there anything interesting in the logs (SME side) and in the event viewer (Windows side)?

[ddougan]

Hi Stefano,

Thanks for your reply. I think it's likely a Windows issue, too, but it doesn't explain why I can map drives on another server, but not on this one from the same PC. Or why it was working and now won't. I've checked the logs on both client and server and see nothing untoward.

The error I get seems like a timeout, as if, although the VPN is active, the client can't see the server on the other side. I thought it might be something related to the "Public"/"Private" network feature that Vista and Win 7 have; but then that doesn't explain why I can map OK on the other client's server.

Regards,

Des

[Stefano]

search for "System error 64 has occurred" with google.. and on M$ kb and technet..

first we have to understand the problem, then we can solve it

[ddougan]

I'd already searched prior to posting here. It basically means that the remote network can't be found (as if it had disconnected). The VPN is still active at this point, I can ping the server using the virtual network's IP address so it makes me wonder if it's related to the Public network feature. But then that doesn't explain why I don't hav the issue on the other server I connected to.

Des

[Stefano]

I'd already searched prior to posting here. It basically means that the remote network can't be found (as if it had disconnected). The VPN is still active at this point, I can ping the server using the virtual network's IP address so it makes me wonder if it's related to the Public network feature. But then that doesn't explain why I don't hav the issue on the other server I connected to.

Des

well.. if everything is working for a customer I would say that it's a connection issue.. this is because we know your client is working, we know that servers are working.. at this point the only difference is the connection towards the remote server.. it could be a mtu issue.. excessive packet fragmentation could lead to this kind of problem

HTH

[ddougan]

Stefano,

It's not an MTU issue - mtu-test runs in the client script and reports OK. I also have added mssfix to the client script, and a WINS definition on the server side script.

None of this has made a difference - it still throws up the error 64 when I try the "net use" command.

Regards,

Des

[Stefano]

ok..

do you agree that it's likely a connection issue?  what about routers/firewalls?

[ddougan]

The firewall is off on the Win 7 box. The SME Server at the other end is the firewall/gateway.

I can't work out why it will connect correctly from XP but I get the issue on Win 7, unless it's a Win 7/Vista issue, but it is clear that others have Win 7 connecting successfully (and of course, I can connect to another client's server and not get the net use error).

I will check if there is  a newer server-side RPM.

Des

[Stefano]

then the only ring of the chain we have not considered is the remote router...

and, of course, the fact that that win7 install has something wrong

[ddougan]

There is no router - the Internet connection is an ADSL modem that connects to the external interface of the server. The internal interface is connected to a small switch. And if it was a routing issue, XP would have the same problem, no?


Thanks,

Des

[Stefano]

yes, it would..

then.. what about that w7? did you try to remove/reinstall openvpn client?

[ddougan]

Yes, I've uninstalled and reinstalled it; I've also tried a different network cable to the client - no change.


Regards,

Des

[Stefano]

ok..

last 2 ideas:
- use tcp instead of udp
- use tcpdump on SME and check for errors

HTH