UltraVNC

...is not their IP problem but SC or repeater issue.

Yes, that's what i thinking about it.

I run the viewer at most with quick option "modem"

The error happens mostly on longer sessions or on filetransfers.
The exact error is: "WriteExact: Socket error while writing."

I have noticed that if ...

@redge:
Thank's for your answer, but the failure appears at any of our customers and from different Control-PC's.
I can't reset the IP-Stack on all cusomer-pc's.

Is it possible, the it was a problem of the repeater?
I will replace the repeater with the newest version and wait, what happens.

No ideas anyway?

We use the old SC with VNCViewer 1.0.2) since 2006 without any big problems for supporting our custumers pc's. Only the support on vista-pc's would not work.

Now I was happy as I get the new SC and see, that it works under vista and win7. But since we use it, we often get a "Socket error while ...

I think, sometimes it will be good to leave a little Message on the client screen, that will be shown until the customer clicks OK, even if the VNC-connection was closed.

This will be usefull if the customer is not at the computer all the time and i can leave him a Message like: "I'm finished. Now ...