Select the option ‘Override automatic cookie handling’ under the Cookies section in the Advanced Privacy Settings window.
Select the ‘Accept’ or ‘Prompt’ option under ‘First-party Cookies.’
Select the ‘Accept’ or ‘Prompt’ option under ‘Third-party Cookies.’ (Note: if you select the ‘Prompt’ option, you’ll be prompted to click OK every time a website attempts to send you a cookie.)
In the window, click OK to exit.
Firefox 3+ (Windows)
Click Tools > Options.
Click Privacy in the top panel.
For ‘Firefox will:’, Select ‘Use custom settings for history’
Select the checkbox labeled ‘Accept cookies from sites.’
Click OK.
Firefox 3+ (Mac)
Go to the Firefox drop-down menu.
Select Preferences.
Click Privacy.
For ‘Firefox will:’, Select ‘Use custom settings for history’
Select the checkbox labeled ‘Accept cookies from sites’
Close the preferences dialog.
Safari (Mac)
Go to the Safari drop-down menu.
Select Preferences.
Click Privacy in the top panel.
For ‘Block Cookies:’, select ‘From third parties and advertisers’