You are correct that clicking Apply or OK in the Options dialog will immediately save settings to the registry. Inventor also saves them as the process is exiting in case the settings have been changed programmatically without using the dialog.
With this in mind, it should be possible to watch the settings change in real-time using the registry editor. Options are saved throughout the HKEY_CURRENT_USER\Software\Autodesk\Inventor\RegistryVersion18.0\System\Preferences key. An easy one to watch is the Application Font value inside the Display sub-key. What happens if you try the following:
1) Look at the current Application Font value in regedit.
2) On the General tab of Inventor's Options dialog, change the Application Font to something distinctive.
3) Click Apply.
4) Back in regedit, press F5 to refresh and confirm that the new font name is being saved to the registry.
If the font name fails to update, it would indicate a permissions issue like Dennis suggested. On the other hand, if the setting updates correctly (but is later forgotten), there might be a loading issue where one source of the settings is overriding another source. This could occur if conflicting settings are being loaded from an XML file.
Possibly a bad User Profile in Windows. Try creating a new user with Admin Privileges and run Inventor to see if the problem persists.
Thanks.
I actually got some help from our software distributor tech support and we ended up re-installing Inventor.
But just for kicks I followed your instructions and verifed that the registry is updating as it should.
I will use that method in the future if I come across similar situations. Thanks again.
Steve
Ive had this issue a couple of times....
User has permissions to edit registry..
Ive got round it by removing all registry for inventor in current user and local machine.
Then for first time fire up of Inventor run as administrator...hey presto fixed for me....
I have came across instances where this doesnt work as well and had to re-create windowsa user profile
Cheers
G