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%1 is not a valid Win32 application. (0xC1) when generating reports and sending to email




I'm receiving the error message "%1 is not a valid Win32 application. (0xC1)" when generating reports and sending to e-mail, or storing it.

However, reports are generated properly in HTML format and can be viewed correctly.

The last time it runs correctly was in 2017/05/17. Since that I receive this error message.

Server info:

Software Version and Server Information

  • PRTG Version: PRTG Network Monitor
  • Auto-update Status: Version successfully installed
  • Operational System: Microsoft(R) Windows(R) Server 2003, Standard Edition (5.2 Build 3790 Service Pack 2 SPV2.0), 2 CPUs (Double x86 Model 6 Step 5), code page "Windows-1252", on "SAMSUNG HD161HJ"
  • Server time: 17/11/2017 10:32:03 (UTC-03:00)
  • CPU Load: 61%
  • Username: PRTG
  • Browser: Mozilla Firefox (Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:56.0) Gecko/20100101 Firefox/56.0)

I've seen other posts about that problem saying to upgrade to version, which corrected this problem. But I've already updated to this version, and others after that, but the problem persists.


-0xc1- mail prtg reports

Created on Nov 17, 2017 12:54:23 PM

1 Reply



Dear Eric,

Thank you very much for your contact.

The error message occurs on systems that run Windows Server 2003. I am sorry, but there is nothing we can do here.

To find further information on how to migrate your PRTG installation with all its sensors, historic data and configuration please see this knowledge base article for further information.

Best regards,

Created on Nov 20, 2017 6:58:07 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.