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PRTG 9 Core Server Service not starting



Hi Guys,

VM is Windows 2008 R2 64Bit.

PRTG version is

I updated PRTG from 8 to 9 many weeks ago and since our virtual environment had a scheduled outage PRTG has not come back online. The Core Server Service will not start. I have been reading up on others suggestions and have tried the following with no luck!!

- Set the PRTG Core Server Service from Automatic to Automatic (Delayed Start)

- Checked the local computer login credentials

- Checked the admin login - cause when I upgraded I used my login

- Disabled Anti-Virus to see if any difference

- In Server Administrator - changed from Port 443 to Port 80

- In Server Administrator - changed from Specify IPs: (my ticked IP) to Localhost:

- Rebooted PRTG VM multiple times after each change

Every time I try to start the core server I get the below error msg!!

Sorry, could not start PRTG Core Server (Web Server) Could not start webserver for Line too long on line 1

Any help would be greatly appreciated!!!

Thanks Faye

core-service prtg ver-9

Created on Apr 18, 2012 2:34:15 AM

Last change on Oct 4, 2012 1:27:53 PM by  Daniel Zobel [Product Manager]

3 Replies

Accepted Answer



Hi Faye,
can you please revert your configuration to one of the auto backups? These are to be found in "<PRTG Data Directory>\Configuration Auto-Backups" . (See this article for details)
Please make a backup of your actual configuration "PRTG Configuration.dat" placed in "<PRTG Data Directory>" then just unzip the last auto-backup and replace the actual config.
Now try starting the core server again.
Best regards

Created on Apr 18, 2012 6:59:18 AM by  Konstantin Wolff [Paessler Support]



the same with you,anybody can help us .... ?

Created on Nov 20, 2012 6:26:27 AM



have you tried the solution suggested above?
Best regards

Created on Nov 20, 2012 7:28:41 AM by  Konstantin Wolff [Paessler Support]

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.