Guan Ming Teo commented on a problem where Leopard erroneously installs PowerPC versions of two virtual private network (VPN) files on Intel Macs. He tried the suggestion on our Leopard VPN Reports page, but found that it made the problem worse. He found another solution:
Just letting you know I tried this:
1. Removed my VPN connection and keychain password---anything I could find that was to do with the VPN
2. Replaced libssl.0.9.dylib and libcrypto.0.9.dylib (I couldn't find any libcrypt.0.9.dylb so I figured it was a typo.) I didn't use any repair permissions thing, I just did it all in Terminal and changed owner & group back to 'root' and 'wheel' respectively. I took a backup copy of the originals sitting there so I could tell what the permissions were
3. Tested regular PPP connection worked
4. Created VPN connection
I think it actually made it worse; before, I could stay connected as long as I didn't actually try to send *any* data through. Now when I connected, it would drop out immediately.
I swapped it back to the original files.
I did end up finding out that I was trying to connect to a Windows VPN server and going by this article.
It says "Microsoft Windows Server 2003, Microsoft Windows 2000, and Microsoft Windows XP [ ... ] use a fixed MTU size of 1400 bytes for all VPN connections."
So I customized a new Location with a smaller MTU size and whenever I need to VPN in, I switch to that Location, and everything works.
I have described all my problems with my particular PPTP VPN at my blog.
If you've seen this problem