Good evening,
I installed Prince on a

Windows Server 2012 R2 Standard
with IIS 8.5.96

I set Full control permissions to Everyone on whole C:\Prince folder, subfolder, etc...
I tried 64 bit and 32 bit versions, I downloaded and registered DLL for ActiveX using.

I checked enableParentPaths in IIS/ASP and Enable32bitApplications in IIS/Application Pool/DefaultAppPool.
I set Managed Piped Mode on Classic in
I checked enableParentPaths in IIS/ASP and Enable32bitApplications in IIS/Application Pool/DefaultAppPool

Still this sample code return Unsuccessful and won't log.

Can anyone help me?

<%
Dim pr
Dim res

Set pr = Server.CreateObject("PrinceCom.Prince")
pr.SetPrincePath "C:\Prince\engine\bin\prince.exe"
pr.AddStyleSheet "C:\Prince\css\test1.css"
pr.AddStyleSheet "C:\Prince\css\test2.css"
'pr.SetEncryptInfo 128, "password1", "password2", true, true, true, true
pr.setlog("C:\prince\log.txt")

If pr.Convert("C:\Prince\examples\magic.html", "C:\prince\output.pdf") = 1 Then
res = "Successful"
Else
res = "Unsuccessful"
End If

response.write res
%>

Hmm it sounds like you know more about IIS and ASP than I do. If it's not failing on the CreateObject or subsequent method calls then it sounds like the COM interface is okay, but maybe it can't invoke the Prince executable later in the Convert method. Are there any errors or exceptions in the server error log?

Thanks for your reply.

No exceptions in server error log.
The strange thing is that it seems ignore "pr.setlog("C:\prince\log.txt")" even if I change the path. It won't log.
Any way to activate a debug mode?

Are all Prince's files in "C:\prince\" (installation path) or maybe I'll find some libraries in some other place?
Which user uses ActiveX object (DLL) to call Prince's methods and perform operations?

The ActiveX object will attempt to run the Prince engine executable, and if that file can't run then no log output will be generated. Can you successfully run Prince\engine\bin\prince.exe from and command-line manually?

Ok, I found out the problem and solved it.

The convertion operation was made from an url non reachable from server side, 'cause it was the external web site url. I simply changed to http://localhost/... and it solved it.
Unfortunately it doesn't seem to log but it doesn't matter.

Thank you very much!