Outlook delay when typing in the address fields

Microsoft Outlook delays when I type in the address fields. I have found 3 possible problems for this:

1. Mcafee antivirus.

Solution
Click Start, Programs, McAfee, VirusScan Console.
Right-click Buffer Overflow Protection and select Properties.
Under Buffer overflow exclusions, click Add, type the process name and click OK.
Click OK.

2. Outlook addin

Solution
In Outlook 2007, go to Tools, Trust Center
Click on the Add-ins section
Click on the add-in you want to disable and then click on the Go.
You will be presented with a list of addins just uncheck the box to disable the addin
restart outlook.

3. Outlook autocomplete/cached email addresses.

close Outlook
open windows explorer and go to "%APPDATA%\Microsoft\Outlook"
rename Outlook.NK2 Outlook.NK2.old
restart Outlook

Hopefully one of these will help you as it did me.