Win32 application that opens PDF files using the Windows API ShellExecuteA.

We are the developers of a Win32 application that opens PDF files using the Windows API ShellExecuteA.

Adobe Acrobat Reader DC (version 2018.011.20040) is installed in Windows to open PDF files.

We have a 64-bit Windows 10 Home machine (version 1803, OS build

1. 17134.137) with two copies of our application - Both copies are the exact same version of our application.

When we run the application normally (ie. NOT as an Admin user), both copies of our application are able to open PDF files successfully.

However, on one of the copies of our application, if we run the application using the "Run as Administrator" Windows option, when we try to open a PDF file, ShellExecuteA does NOT return any error but the PDF file does not open AND Acrobat is then "stuck" from that point forward and cannot open any PDF file using ANY user context. We are forced to restart Windows to allow Acrobat to work again.

On the other copy of the application when "Run as Administrator", the problem does NOT happen.

In both cases, the application and PDF files are identical - The only difference is the folder they are run from. We checked the rights for both folders and they are the same.