I used Visual Studio 2013 for developing plugin from Adobe Reader DC SDK in the development computer. I built the sampe code - SampleExtn. Put the *.api into Acrobat Reader DC's plug_ins directory. Open Acrobat Reader and it can work. Show the "Acrobat SDK" in menu bar.
But when I installed the same Acrobat Reader DC in the another computer - testing computer. Copy the same *.api into Acrobat Reader's plug_ins directory. Open the Acrobat Reader and cannot show "Acrobat SDK" menu.
The two computers have the windows 10 OS and Acrobat Reader DC is 2020.013.20066.
1. Is the plug-in reader enabled?
2. SampleExtn uses the sandbox. Is the sandbox enabled?
1. how to enable? I don't do anything in workable acrobat reader.
2. yes. sandbox is enabled.
Plug-in loading and initialization
When Acrobat or Acrobat Reader is started, it searches the plug_ins directory (co-located with the Acrobat executable) to locate and load plug-ins. In addition, Acrobat or Acrobat Reader searches folders that may be located within this folder. This search goes one level deep.
Acrobat and Acrobat Reader display a progress message in the bottom line of the splash screen at start-up. As each plug-in is loaded, the progress message shows the plug-in name. No plug-ins are loaded if the Shift key is held down while Acrobat or Acrobat Reader start. Also, if Acrobat or Acrobat Reader are running in certified mode, no third-party plug-ins are loaded.
I don't know how they work. don't know if it is related with my problem.
It is supposed to be impossible to load a plug-in to Acrobat Reader, unless it has been reader enabled. The SDK gives details. This needs a license from Adobe, and a fee. I do not know why it would load on the first machine, that sounds like a bug. You must use paid-for Acrobat for your testing.
PS from your original title "Adobe Reader DC SDK", details matter.
1. There is no such product as Adobe Reader DC. The name of the free product is now Acrobat Reader DC. The name of the paid product is just Adobe Acrobat.
2. There is no SDK as "Adobe Reader DC SDK" or even "Acrobat Reader DC SDK". It is the Acrobat SDK, and you are expected to have Acrobat - not Reader.
Do I need to download Acrobat product and it is free?
To develop plug-ins for Acrobat or Acrobat Reader you will need Acrobat. It is not free. The SDK is a marketing tool for Acrobat, if you want to see it that way. To make plug-ins that load in Reader you need a special license and fee. The license is only given in certain cases - for example, you must not make a plug-in for Reader that would save people from buying Acrobat by allowing editing!! The fee is variable, up to $25,000 per year for DRM plug-ins.
Have you build a Release or Debug version of the plugin?
I built debug version.
For the use of a non-development machine you must build a Release version of the plugin.
[Question moved to the Acrobat SDK forum]
It is fine, when I build the release version.