Error using COM Interface


Hi, i’m using pdfcreator as virtual printer with success. And now i’m looking for COM Interface to integrate in a windows form application ( framework .net 4).
As described in documentation i found example in COM Scripts folder but i cannot run any sample project.
In COM_TestForm project if i start debug and press the TestPage2PF button the program stop at line:


with error “System.Runtime.InteropServices.COMException (0x80004005): Object reference not set to an instance of an object.”

Same error if i run C# COM_TestForm sample.

Any suggestions
Thank you


I got the same problem. None of the examples work.

I tried adding file to the queue (see code), but still get the same error:

var pdfObj = new PdfCreatorObj();

Stack trace:

   at pdfforge.PDFCreator.Core.ComImplementation.PrintJobAdapter.DoConversion(Job job, String targetFilename)
   at pdfforge.PDFCreator.Core.ComImplementation.PrintJobAdapter.ConvertTo(String fullFileName)
   at pdfforge.PDFCreator.UI.COM.PrintJob.ConvertTo(String fullFileName)
   at COM_TestForm.Form1.testPage_btn_Click(Object sender, EventArgs e) in C:\Program Files\PDFCreator\COM Scripts\C#.Net\COM_TestForm\COM_TestForm\Form1.cs:line 81
   at System.Windows.Forms.Control.OnClick(EventArgs e)
   at System.Windows.Forms.Button.OnClick(EventArgs e)
   at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
   at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
   at System.Windows.Forms.Control.WndProc(Message& m)
   at System.Windows.Forms.ButtonBase.WndProc(Message& m)
   at System.Windows.Forms.Button.WndProc(Message& m)
   at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
   at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
   at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
   at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
   at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(IntPtr dwComponentID, Int32 reason, Int32 pvLoopData)
   at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
   at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
   at System.Windows.Forms.Application.Run(Form mainForm)
   at COM_TestForm.Program.Main() in C:\Program Files\PDFCreator\COM Scripts\C#.Net\COM_TestForm\COM_TestForm\Program.cs:line 18
   at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
   at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
   at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
   at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Threading.ThreadHelper.ThreadStart()

How to fix this?


I have the same Problem with function "ConvertTo(…)


Still having this issue. Anyone have a solution??


I have one same issue with me

Message = “Referência de objeto não definida para uma instância de um objeto.”
Source = “PDFCreator.ComImplementation”
StackTrace = " em pdfforge.PDFCreator.Core.ComImplementation.PrintJobAdapter.DoConversion(Job job, String targetFilename)\r\n em COM_TestForm.Form1.testPage_btn_Click(Object sender, EventArgs e) na C:\Program Files\PDFCreator\COM Scripts\C#.Net\COM_TestForm\CO…


I have same problem here.
I am using PDFCreator 2.4.1, Win 8.1, COM using LotusScript (very similar to VBA).

At line with .ConvertTo(fullfilename) it raises error, but PDF file is created. But for production it is useless…


It is still not fixed - same problem in version 2.5.1 and 2.5.2.
Have you found a solution or workaround?

Best regards,


I got the same error with 2.5.2

The problem took over half year, any one fix it?


Hi, I got the same issue.
Any solution?



the error should be fixed for all COM access except VBA, which seems to be violating the COM principle (The essence of COM is a language-neutral way of implementing objects). So far it is unclear why there is a problem with VBA access, if you’d like to use VBA, please downgrade to PDFCreator 2.4.x for the moment.

Best regards,



I’m working in c# .NET 4.5, windows application.
It doesn’t work even with 2,4.x version.
I got the following error code: -2147467259, object not set to an instance of an object.
The error occurs invoking ConvertTo function.

var jobQueue = new Queue();
if (!jobQueue.WaitForJob(10))
var printJob = jobQueue.NextJob;



did you already come across ?

Best regards,



It works!
Thank you very much.