can't connect to webservice

[ike]

Hello,

I have a problem with a webservice for one of my users.
The webservice provides a way to create backups on our servers.

When this user starts the backup he gets a "InternetWriteFile error code:
12031"

The strange thing is when I use vnc to take over his system, the service
works fine.

The service only uses ports 443 (https) and 21 (ftp). But not 5800 or 5900
for the vnc.

Right now I don't know where to look.

Any ideas?

Thanks,
Ike Casteleyn
Compufti software