Here is an alternative to disabling UAC - an option some call "Quiet Mode" - and essentially leave UAC enabled but elevates the all administrator accounts to assume it is okay to run the item in question. Note, this will effectively disable the protection that UAC provides, but will not disable IE's Protected Mode.
UAC (User Account Control) is the 'feature' that causes those annoying Windows Vista pop-up warnings that present when you try to perform certain functions or start certain programs that tell you permission is required to perform the function or open the program. These pop-ups only happen when you have UAC turned ON, which is the recommended setting to 'protect' your computer--or more precisely to stop you from installing anything onto your computer that has the potential to cause harm.
Advanced users can safely turn this feature OFF, as it is assumed that advanced users will know what should and should not be installed on their machines, and they know not to click on links in email from senders that they do not know, etc. So, it would seem simple enough for advanced users to just turn UAC off and not be annoyed by these warning pop-ups--but here comes the catch: There are some third party products that will not work properly with UAC turned off. One of these popular products is Intuit's QuickBooks. (I've written about this here.)
So my original 'solution' was to turn UAC off for most of the time and then turn it on when I needed to use the functions within QB that required it. This seemed to work just fine until I started noticing some strange behavior on my computer--new programs wouldn't install properly, some programs started to act up, etc. Long story short--turning UAC on and off more than once corrupts the system registry by stripping all of the user permissions off of all of the keys. This is now a known issue and I have been in contact with Microsoft about whether this issue was addressed in SP1 or any other hot fix since encountering the problem and writing about it in the article linked above.
To date, everyone I have communicated with at MS has acknowledged the problem, but no one has been able to say whether it has been addressed or not. However, I was presented with a way to get around the annoyance of the warning pop-ups with UAC turned on! This was exciting news to me, as I really don't care if UAC is on or off as long as the pop-up warnings go away.
It turns out there is a registry key that can be changed that will effect this pop-up behavior--in fact it will turn it off completely even when you have UAC turned on. The name of the key value is ConsentPromptBehaviorAdmin.
Here is an alternative to disabling UAC - an option some call "Quiet Mode" - and essentially leave UAC enabled but elevates the all administrator accounts to assume it is okay to run the item in question. Note, this will effectively disable the protection that UAC provides, but will not disable IE's Protected Mode. (Open the registry editor and search for the "value" "ConsentPromptBehaviorAdmin".)
Key: SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System
Value: "ConsentPromptBehaviorAdmin"
Type: REG_DWORD
Size: 3
Data: This MUST be a value in the following table.
Value: 0x00000000
Meaning: This option SHOULD be used to allow the Consent Admin to perform an operation that requires elevation without consent or credentials.
Value: 0x00000001
Meaning: This option SHOULD be used to prompt the Consent Admin to enter their user name and password (or another valid admin) when an operation requires elevation of privilege.
Value: 0x00000002
Meaning: This option SHOULD be used to prompt the administrator in Admin Approval Mode to select either "Permit" or "Deny" an operation that requires elevation of privilege. If the Consent Admin selects Permit, the operation will continue with their highest available privilege. "Prompt for consent" removes the inconvenience of requiring that users enter their name and password to perform a privileged task.
Here is a link to the original article on Microsoft Developer Network.
