Hello Rita.

What changes are this exactly? Did they happen after you updated to 3.6.4? (The latest version is 3.6.6, by the way) Maybe it's the plugin container, that serves to isolate plugins, in order to prevent them from crashing Firefox, when they crash. See this page for info on that.

Check that you do not run Firefox as Administrator. Right-click the Firefox desktop shortcut and choose "Properties". In the Compatibility tab, make sure that Privilege Level: "Run this program as Administrator" is not selected. You also need to check the Properties of the firefox.exe program in the Firefox program directory.

If you have Windows-7: Home Basic and Home Premium this works.

1. Create a new text file

2. Copy the text below into it.

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System] "ConsentPromptBehaviorAdmin"=dword:00000000

3. Save as, e.g. DisableUACadmin.reg The reg extension is recognized by the registry editor.

4. Double-click your file and accept everything.Then do PART II below.

If you have Windows-7: Professional (Business), Enterprise and Ultimate Editions this works.

1. From the START MENU open the Control Panel and click on the Administrative Tools icon.

2. Double click on Local Security Policy to open it.

3. Browse down to Local Policies and then down to Security Options

4. In the list find: “User Account Control: Behavior of the elevation prompt for administrators in Admin Approval

Mode” and double-click on it.

5. Using the dropdown window change the setting to “Elevate without prompting”.

6. Close out all your windows and do PART II below

PART II

For all versions of Windows-7, now you can right-click the FireFox icon and select properties. Click on the Compatibility tab and select "Run this program as an Administrator".

No more UAC for Firefox.