This article was created in response to a support issue logged with K2. The content may include typographical errors and may be revised at any time without notice. This article is not considered official documentation for K2 software and is provided "as is" with no warranties.
The PDF Conversion does not work. When accessing the PDF conversion target URL from the K2 server under the K2 service account, it shows the following error in the browser:
This page can’t be displayed. Turn on TLS 1.0, TLS 1.1, and TLS 1.2 in Advanced settings and try connecting to https://hostname again. If this error persists, it is possible that this site uses an unsupported protocol or cipher suite such as RC4 (link for the details), which is not considered secure. Please contact your site administrator.
Enabled ciphers registry keys (HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\Schannel\Ciphers) show that RC4 is disabled (more details on this - Disabling RC4).
In addition to the symptoms mentioned above, the following error gets logged in the host server log:
"Error","General","28083","ExtenderExecuteError","ProcessInstance.HandleException","28083 ServerEvent: Message: Failed to convert HTML to PDF.; ServiceName: PDFConverterService; ServiceGuid: 99ae73bf-b5df-44dd-932e-615bb343585b; InnerExceptionMessage: ; Message: Failed to convert URL to PDF.; ServiceName: PDFConverterService; ServiceGuid: 99ae73bf-b5df-44dd-932e-615bb343585b; InnerExceptionMessage: ; Message: Could not get image from url. Could not get image from url. The URL is not accessible. Status code 0x800C0005.The server or proxy was not found.; ServiceName: PDFConverterService; ServiceGuid: 99ae73bf-b5df-44dd-932e-615bb343585b;
This issue can occur when bindings for K2 are configured to listen only on an external server IP and the K2 server has hosts file entry for K2 farm FQDN resolving it into its loopback IP address (127.0.0.1) - in this case IIS will be receiving HTTPS requests on the IP it is not listening on, which will result in the symptoms described above.
To resolve this problem you need to adjust the K2 site bindings to listen on all unassigned IPs and also to create a default HTTPS site. This should resolve the RC4 error and make K2 sites accessible from K2 server and consequently resolve the error with PDF conversion.