Hello Mario,
There are almost no situations where a re-installation is needed. The manager can usually fix all these issues. For this one in particular, just create a dummy custom field, to make the custom properties list dirty (in order to get the apply button active) and apply these changes. You can then remove the dummy field. Check also if all the properties you want visible in the details pane are checked in the "details pane items" tab.
This situation may occur when the shell default PDF reader is changed and also with major Windows updates.
Regarding your license password. You may always request assistance, from your license registered email address, to get that info back.