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Unable to map drives over VPN?

I hope someone here may be able to shed a bit of light on this problem...

I'm currently working as a freelancer for a large company, who have provided me with a loaned notebook computer which I need to use to be able to log on to their corporate network from home.  I can connect this to my router at home no problem (via wifi or using an ethernet cable) and then connect to the company's VPN using the provided Cisco VPN client (v5.0.07.0290).  That all works fine apparently, I can fire up Outlook and use my company email as if I'm in their office.  However the big problem is that I'm unable to access various mapped drives on their network, which I need to be able to do to run a particular piece of software.  I've sought assistance from their help desk, however they have swapped out the machine (no effect) and have tested it (connecting it to their VPN via wifi while in their office) and it works fine; so they are giving me the oh-so-typical answer that it must be something to do with my setup at home, or my ISP, and it's therefore outwith their control, so tough!

Currently I'm having to do my work in their office, which isn't ideal, and I'd really like to get this fixed.  The odd thing is I worked for them before under similar circumstances abouyt a year ago with no problem at all (unfortunately I can't pinpoint whether anything specific (eg router) has changed at my end since that time, but I concede it's conceivable).  I'm not much of a techie, but does this symptom actually make any sense to anyone?  Is it plausible that the problem is my "fault"?  As the laptop kit is all provided by the company and is pretty locked down, I can't do much tweaking.

Basically when I log on, it runs a batch file which attempts to set up the drive maps, but this fails with the words "Drive P is NOT connected".

My router is a Buffalo model running DD-WRT v24-sp2 firmware, in case that helps... if you need any further info about my equipment and configuration, please ask!

Would be very grateful for any help.



Cisco Employee

Unable to map drives over VPN?


Without data to go on I would say the most resonable is a MTU problem, typically seen when folks try to RDP to things over internet.

(Services use high MTU/MSS and set DF-bit , which makes thing impossible to transfer bigger packets over VPN in some cases).

You should be able to lower MTU/MSS on you PC. Now the actual way to do this you should be able to find by checking around your OS vendor's pages.

Again, I'm purely making a (hopefully) educated guess.

The way to confirm would be to sniff traffic on VPN adapter and inside of VPN headend in use...

As a workaround, if possible try using FTP, some FTP services do not stamp IP packets with DF-bit.


Re:Unable to map drives over VPN?

In additon there could be other issues such as vpn filters or the networks are not passed down to the client.

Testing over internal wifi is a questionable approach because traffic used to map network drives can be using the wifi and not the vpn client. In the end you will have to work with your technical teams for resolution.

Sent from Cisco Technical Support Android App

Tarik Admani *Please rate helpful posts*
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