It is a problem I’ve had at work many times and I hope this can shed some light on a few people who need it. If you install Magento and cannot login to the admin panel inside of Internet Explorer, it is a cookie issue. Here is what you can do to fix it.
- Make sure your server’s time settings are the same as your time settings inside of Magento. This will effect your cookie expiration.
- Set your cookie expiration date to a longer life cycle as well.
- Make sure cookie domain is explicitly set.
- Restart your browser and clear your cache.
- Make sure your domain has at least one dot (.) in it. (this especially if you are using localhost).