This issue happens when you install Post Manager 1.2 on a machine that already has an older version installed.
This is a result of a conflict with the older version of Post Manager. We are currently working on a solution, but in the meantime, you could try to uninstall Post Manager, or delete it’s folder manually, then run the installer again.
Uninstalling
After installing Post Manager 1.2 and encountering the issue above, simply just uninstall it from Windows’s Add/Remove Programs, then just run the downloaded installer again.
Removing Manually
To do that, go to C:\Users<your username>\AppData\Roaming\Adobe\CEP\extensions and delete the folder called “com.pulze.postmanager”, then just run the downloaded installer again.