"But now it is not visible after update to (14.4.2). I am not able to see files in spite of changing the install parameters to program files"
Could you please check both Program File folders (Program Files/Program Filesx86). On a 64-bit OS any 32 bit application
is automatically redirected to Program Files x86. Also please note that when you upgrade your application the update itself will use the installation path defined in the starting version installation.
"How can I check for an update of my plugin manually"
You might want to consider integrating the updater functionality in your application.
Please have a look at the following article for more information How to integrate the Advanced Updater with my application
If you are still encountering issues, please send us the .AIP (project) and a verbose log
of the installation to support at advancedinstaller dot com so we can investigate them?