simple VPN between windows 8 clients

Need more info. What VPN server/client software used. IP addresses/subnets (both LAN/VPN IPs).
Did you test the shared folders correctly in a LAN environment yet?
Check if firewall makes a distinguishment between the VPN connections (if so, check if firewall rules for these VPN adapters)

Can you access and share by IP address?  In this setup, DNS would not be automatically.

Access a share as:  NET USE Z: \\ip of other computer\folder.  What error, if any, do you get?

Make sure in advanced network sharing options that Network Discovery and File and Print sharing are enabled. Homegroup should be disabled.

Thank you for the fast comments but i'm already at home.
When i'm back at work in the morning, i'll try to reply to the asked questions.
Thanks in adavance.

I've openend incomming connections to windows 8 for 1 vpn user.
The folders are already shared in a network and are working properly.
I added the vpn user to the rights of the folder with full read/write access.
My firewall is disabled at the moment until i've got it working properly.
The local sharing works perfectly with my firewall enabled.
When i do net use, the disk is available on my computer but i can't access it.
When i try to access the folder i've get an no access error.

I also have done an ipconfig and netstat on both computers.
ipconfigclient.txt
ipconfigserver.txt
netstatclient.txt
netstatserver.txt

When i do net use, the disk is available on my computer but i can't access it.

Until you can do this, you will not be able to access shared folders.

So then, open a command prompt and from the 192.168.1.x computer type:

NET USE Z: \\192.168.18.105\foldername  and enter.

What error number do you get?

I don't get an error message.
It just sits there but when i click the message promt says that i don't have access.

If that is true, then your tunnels are not working properly.

From 192.168.1.x open command and ping 192.168.18.105  and enter.

What answer do you get?

With respect to Windows 8.

1. These will be Windows 8 Pro and certainly not Windows 8 Home for this use. Correct?

2. Read my article on Folder Sharing for Modern Machines and work through all the settings on both machines.

https://www.experts-exchange.com/OS/Microsoft_Operating_Systems/Windows/A_16639-Folder-sharing-on-modern-machines.html

If i ping to my server or client, i've got an reply (4times)
The server is running windows 8 pro and the client is an regular windows 8.
I will read your article and check if everything there is ok.
I hope this fixes my problems.

The client computer has windows 8 home version and the server has windows 8 pro.
I already read your article about folder sharing and the folders where already shared the right way.
If i ping from the client to the server and vice versa, i got a reply.

On the client: Start > Run > \\192.168.18.105 (press enter)
You should get at least a login prompt ?

i've get an "error pad" when i do run > \\192.168.18.103
but when i enter \\192.168.18.103 in explorer i see a list of all shared folders on the server.
When i click the folder i've get an no access to \\192.168.18.103\foldername

Are you connecting from Home to Pro (server)? Probably.

Try connecting from Server (Pro) to Client (Home) using NET USE and let us know about errors and answers to the command.

I do not ever recommend Windows Home.