[Samba] Samba 4.1.6 can not read from share

[Johan Hendriks]

Hello all.

I have a strange issue with my samba machine.
I upgraded from 3.6.22 to 4.1.6, everything is looking good. wbinfo -u 
shows me all users, wbinfo -g list all groups, id user gives me all the 
info.
I can browse the share without problems. I can delete files from the 
share, i can put files on the share BUT as soon as i open a file, or 
when i try to copy a file from the share to the windows machine i get 
error messages on the windows client.
The error in Dutch is:

Er is een probleem met het krijgen van toegang tot I:\data\filetocopy
Zorg ervoor dat de computer verbonden is met het netwerk en probeer het 
opnieuw.

In my best translation it is:

There is a problem accessing the file I:\data\filetocopy
Make sure your computer is connected to the network and try again.

I have rebuild samba, i have removed all tdb files and joined the domain 
again, I also minimized the smb4.conf file but the problem stays.
I see no core dumps or other errors in the log.

Can someone help me with this.
I am on FreeBSD 10-Stable

regards
Johan