Hi Nicola,
Thanks for contacting Syncfusion support.
WebKit HTML converter requires OpenSSL assemblies for converting https sites. So, please make sure the assemblies are available in the machine where the conversion take place.
1. You can install the OPENSSL library by downloading its setup from the below link,
(OR)
2. The required OpenSSL assemblies below can be placed in the Windows system folder (for 64-bit machine, it should be place in $Systemdrive\Windows\SysWOW64 and for 32-bit machine, it should be place in $Systemdrive\Windows\System32),
1. libeay32.dll
2. libssl32.dll
3. ssleay32.dll
If still the blank PDF occurs even at the presence of the OpenSSL assemblies, please provide the input URL, code snippet and environment details such as OS, bit version, culture settings etc., so that it will helpful for us to proceed further.
Regards,
Prakash V