certmgr.exe was missing when I tried to create certificate using the tool as shown above.
I installed visual studio community edition and then created certificate using the tool.
Everything is working fine now.

Thanks for the help!
-Roy
I humbly ask for your guidance and suggestions through this issue.[ Build_MSIX_APPX ]
Detecting Signtool compatibility
Detecting MSIX/APPX incompatible resources
ERROR: UWP Package. The package logo is missing '125, 150, 200, 400' image scale(s).
ERROR: UWP Application. The application 'FileMover.exe' is missing 125, 150, 200, 400 'Medium' image scale(s)
ERROR: UWP Application. The application 'FileMover.exe' is missing 125, 150, 200, 400 'App Icon' image scale(s)
Creating resources.pri file(s)
Building MSIX package:
C:\Users\timotej.jakimovski\Documents\Advanced Installer\Projects\MSIx-Test\Build_MSIX_APPXSetupFiles\MSIx-Test-x64.msix
Preparing files
Preparing data for MSIX package
Creating AppxManifest.xml file
Validating AppxManifest.xml file
Creating registry file(s)
Creating [Content_Types].xml file
Creating MSIX file
Signing MSIX file
The digital signing of the MSIX/APPX failed. Error message: 'Done Adding Additional Store
Number of errors: 1
SignTool Error: This file format cannot be signed because it is not recognized.
SignTool Error: An error occurred while attempting to sign: C:\Users\timotej.jakimovski\Documents\Advanced Installer\Projects\MSIx-Test\Build_MSIX_APPXSetupFiles\MSIx-Test-x64.msix
File "C:\Users\timotej.jakimovski\Documents\Advanced Installer\Projects\MSIx-Test\Build_MSIX_APPXSetupFiles\MSIx-Test-x64.msix" can not be signed!
For a possible solution please check our Digital Signature FAQ from:
https://www.advancedinstaller.com/user- ... ature.html '
Build finished because an error was encountered.