What is this?

This knowledgebase contains questions and answers about PRTG Network Monitor and network monitoring in general.

Learn more

PRTG Network Monitor

Intuitive to Use. Easy to manage.
More than 500,000 users rely on Paessler PRTG every day. Find out how you can reduce cost, increase QoS and ease planning, as well.

Free Download

Top Tags

View all Tags

What is the relationship between .dat file and .old file?



The following is a description of the old file in the manual.

PRTG Configuration.old : Backup of previous version of monitoring configuration

What exactly does the previous version mean?

Is it possible to restore the configuration even if there is only .dat file without the .old file?


backup installation old restore

Created on Oct 12, 2020 5:40:01 AM

Last change on Oct 12, 2020 5:54:36 AM by  Stephan Linke [Paessler Support]

3 Replies




Thank you for your message.

PRTG saves its configuration every day so when the server has to restart, all your modifications (objects added, removed, modified, etc.) are taken into account.

During this process, PRTG makes a copy of the configuration file used until the backup and renames it to PRTG Configuration.old. The previous configuration file (before being renamed) is also saved in the following folder "C:\ProgramData\Paessler\PRTG Network Monitor\Configuration Auto-Backups".

Regarding your question about the restoration of PRTG with the PRTG Configuration.dat file, yes you can. You will then get the latest modifications made in PRTG.

Kind regards.

Created on Oct 12, 2020 9:38:13 AM by  Florian Lesage [Paessler Support]



Only the name is different, is the latest file in the folder the same as the .old file?

When is the specific time for the backup process to proceed?


Created on Oct 13, 2020 12:41:36 AM



The configuration files are different as the .dat contains the current configuration of PRTG. The .old contains the previous version (which was running before the backup).

Regarding the backup schedule, PRTG performs a backup every morning around 3am. Please have a look here: https://kb.paessler.com/en/topic/59619-is-there-a-way-to-schedule-prtg-backups

Kind regards.

Created on Oct 13, 2020 6:13:02 AM by  Florian Lesage [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.