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How can I downgrade from 18 to 17 version?




I've tried to downgrade from latest 18 version to, but I receive error, when I start Core service:

Couldnot start webserver for newid: -1000 newid: -3 newid:300 Could not load "notification300: Notify-Type "slack" not found"

prtg server update

Created on Sep 3, 2018 10:25:43 AM

3 Replies



Dear Greg,

Thank you very much for your contact.

Please allow me to ask for what reason you downgraded PRTG?

Without seeing any log files I assume that the problem is that the most recent configuration file of was already opened running PRTG v18.x.
PRTG v17 has different data tree version which makes it necessary to also restore the compatible PRTG configuration file from the Configuration Auto-Backups directory within your PRTG data directory from a time before you installed v18.x.

Please exchange the configuration file and then restart PRTG's services. If you encounter additional issues with your installation, please don't hesitate to response.

Best regards,

Created on Sep 4, 2018 10:01:09 AM by  Sebastian Kniege [Paessler Support]



Im getting the same error, im not clear from your message which date/file i need to pull from config-auto backup to get past this error. i have a: PRTG Configuration (Update to and a: PRTG Configuration (Update to

and others from a few days prior, all are giving me the same error when i try swaping the .dat file

This is a new install of v18 and ive already added about 20 devices and dont like the new interface, so im trying to go back to v17. let me know pls. tks

Created on Sep 27, 2018 2:13:30 AM



Hello Jim,

It's important that PRTG Core Server version matches the tree version of the PRTG configuration.dat file.

Did you already downgrade your PRTG Core Server to version again? If so, check the backup directory of the configuration files. The backups are usually labeled to easily identify which one is used for which version. Please make sure to revert a configuration file from the time as you used PRTG

Anyways and as I already wrote you vie email a couple of days ago. Even for me working with the Facelift was unfamiliar at same points for quite a while. However please note that we officially only support the very last stable version of PRTG. If you stick to PRTG (which was a very reliable one though), you won't receive any updates in future. Sticking to the facelifted version is probably the best approach.

Best regards,

Created on Sep 27, 2018 9:09:10 AM by  Sebastian Kniege [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.