The main reason behind this type of issue is that Windows or a protection utility is not allowing NoteTab to save its settings to disk. Usually this happens because NoteTab is configured to save its settings under the Program Files folder. When you are running Windows 7 or Vista, or running Windows XP/2000 without administrative privileges, or using certain anti-virus products, programs cannot save data in protected folders, like Program Files and WINDOWS.
By default, NoteTab 7 (as well as 6 and 5) are designed to store settings under the Application Data folder (AppData\Roaming on Windows 7 and Vista). However, if you’ve installed NoteTab over version 4 to retain your settings, NoteTab will work the old way and continue to save settings under the Program Files folder. The solution is to move NoteTab’s INI file to the Application Data folder.
If you're using a recent version of Windows then the application data folders are usually located in here
C:\Users\<USER>\AppData\Roaming\
The settings file for NoteTab Pro is NotePro.ini. For NoteTab Std it's NoteTab.ini.