Registration Free COM

PDF-XChange Viewer SDK for Developer's
(ActiveX and Simple DLL Versions)

Moderators: TrackerSupp-Daniel, Tracker Support, Vasyl-Tracker Dev Team, Sean - Tracker, Chris - Tracker Supp, Tracker Supp-Stefan, Ivan - Tracker Software

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Joined: Wed Sep 30, 2009 6:53 pm

Registration Free COM

Post by jeffp » Mon Jun 24, 2013 9:15 pm

I'm using the Registration Free method for your ViewerAX. It seems to work great most of the time. But I have had a few customers where this method doesn't seem to work. The form where the ViewerAX is suppose to appear just contains an Icon, but no control.

I'm pulling my hair out trying to figure out what settings in their OS are causing this not to work. Does it have anything to do with UAC? I've both enabled and disable UAC on my OS and it works fine in both cases.

I can get it to work if I register the COM control in the normal way, but I'd like to figure out why in some cases the registration free method doesn't work. That latest was on a Win8 machine, but I think I've had it come up on Win7 as well.

Again, it is rare (or at least the one's reported are). Have you had other reports of this? Or can you give me some more guidance on what I need to check on the OS to ensure that it will work in all cases.


Nico - Tracker Supp
Posts: 220
Joined: Fri May 18, 2012 8:41 pm

Re: Registration Free COM

Post by Nico - Tracker Supp » Tue Jun 25, 2013 12:50 am

Hi Jeff,

Thank you for your post.
If you see an icon instead of the control that means the PDFXCviewAx.dll library is not found.
We have seen this issue happening when the manifest used for Click-once (COM-registration free) was not properly written.
Please don't use both methods at the same time, make sure the server (PDFXCviewAx.dll) is unregistered before using the COM-registration free method.
Please try the following:
  • Unregister the server from the command line: regsvr32.exe /u "PDFXCviewAx.dll", and make sure there is not any reference to the server in the Windows registry, or if you have installed the SDK by using an msi or exe installer, run the proper msi and exe uninstaller program.
  • Follow the "Registration-Free Deployment" guidelines at the Viewer ActiveX Manual (PDFV_AX.pdf, page 4)
  • Make sure the template for the manifest looks like the example provided in the SDK at "C:\Program Files\Tracker Software\PDF-XChange Viewer SDK\Examples\Registration-Free COM" folder
  • Also, make sure the following files are in the same folder (ActiveX and .exe versions should match as well as the architecture - 32 or 64 bit):
The UAC should not have anything to do with the registration-free process. We have used the registration-free method in both Windows 7 and 8 with success.
Please feel free to come back if you have any questions.

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Joined: Tue Jul 02, 2013 10:06 pm

Re: Registration Free COM

Post by RMan » Mon Jul 22, 2013 4:14 pm

Depending on what language you wrote your program in you might want to check the length of your manifest files. I remember some languages like VB6 will not give an error but the manifest file won't work properly unless it's an increment of 4 bytes in size. So 40, 44 work but not 42 bytes.

I have also seen where some of the antivirus software might be shutting down the PDFXCView.exe process that is spawned from your program. So you might want to check and see if their antivirus has a log of what programs it has shut down and tell it to ignore that program.

Nico - Tracker Supp
Posts: 220
Joined: Fri May 18, 2012 8:41 pm

Re: Registration Free COM

Post by Nico - Tracker Supp » Mon Jul 22, 2013 5:59 pm

Hi RMan,

Thanks for the post and the information provided.

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