STOP - App does not launch

[lisaacso]

Just upgraded my TS-219P to 4.0.7 (20140412).
When I now launch Surveillance Station Pro, I get a webpage tab with this url:

http://192.xxx.x.x:8080/cgi-bin/surveillance/

and the following message:

STOP
Page not found or the web server is currently unavailable. Please contact the website administrator for help.

I have uninstalled /reinstalled the software, restarted the server, etc. to no avail.

Any ideas?

[lisaacso]

Now working.
I had changed to a fixed Ip address but changed back to DHCP.
I also changed the 'Jumbo Frame' to 9000 from 1500, but do not know if that was related to the problem solution. I doubt it.

[AlastairStevenson]

It's a good idea to ALWAYS know the IP address of your QNAP box. Even if you are addressing it by name using a DNS service.
Although a DHCP 'renew' on lease expiry will almost always assign the same address, this is not guaranteed.
If you want to have central control of all the devices on your network (which is a good idea, so you can fairly reliably associate and assign network and security events and rules with the offending device) the use of DHCP reservations in your DHCP server works OK. That's assuming your DHCP server is always responsive.