This article applies to PRTG Network Monitor 12 or later

Check your Anti Virus / Anti Malware Product

Most likely, there is an anti-virus or anti-malware product running on the computer where your PRTG core server is installed, and this product blocks the download performed by PRTG.

For example, we've seen such a behavior on systems running ESET NOD32 Antivirus.

So solve this issue, we recommend you either disable your protection product temporarily during download and installation, or you add the PRTG program directory to the excluded paths, so PRTG's files are ignored permanently. You might also need to explicitly whitelist the paessler.com domain.

The exact settings on your systems will vary depending on the security product(s) you use.

Example: ESET NOD32

In our case using ESET NOD32, it was necessary to enter the advanced configuration mode and add the string *paessler.com* to the "HTTP address management" exclude list of the Web access protection component, in order to successfully use PRTG's auto-update function.

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