What Does "Mixed Redirects" Mean?
A mixed redirect is when there are 2 or more other URLs redirects strung together in a chain, but the HTTP status is not the same for all redirects. At least one redirect in the chain is a 301 permanent redirect and at least one redirect in the chain is a 302 temporary redirect. See "Different Types of Redirects" below for more information on the difference between these two redirection methods.
Why It's Important
Both a 301 and 302 redirect are used for different purposes, and each sends a different message to search engines. If they are both used in the same chain, search engines will not know how to treat the URLs – "Is it actually a temporary redirect or a permanent one? Should we remove the URL from our index or leave it? Do we pass link juice to the target URL or not?" Therefore, we cannot predict how search engines will treat these URLs, and unintended consequences could result.
How to Fix
Take a look at each redirect chain in the table below.
First of all, you may want to consider minimizing the steps in the chain – one redirect is always best. By eliminating the redirect chain in the first place, you will also take care of the mixed redirect problem. This should be your first method if it's possible for your situation. This is especially important if there are more than 3, since search engines could give up following the redirects and may never reach the destination URL. To fix this, consider changing the first redirect step in the chain to point to the last URL in the chain. Be sure to leave the other intermediate steps untouched, as there could be other links that point to these URLs, and you want to be sure these will still resolve correctly as well.
If you leave the redirect chain in place, take a look at the different statuses for each redirect. Decide on whether you want to signal to search engines that this is a 301 or a 302. Then update how you're doing the redirects for the URLs that do not match this status. Most of the time, you will want to update them all to be 301 redirects.
Implementing a 301 redirect is different for each web server. If you're running an Apache web server, it can be done in the .htaccess file. For Windows servers, the redirects can be set up by creating a redirect rule in the Internet Services Manager.
Different Types of Redirects
There are a number of HTTP status codes that could be classified as redirects, but we're generally most concerned with two: 301 and 302. Generally speaking, 301s are best for SEO, but 302s also serve a purpose:
This type of redirect is used to signal that the redirect is permanent - the old URL will not be used again. This is generally the type of redirect you want to use on your site. That's because 301 permanent redirects typically pass all the link juice from the first URL to the target URL. Therefore, when a page moves, it's possible to keep the same ranking position - thus preserving your SEO efforts. It's also a signal to search engines that the original URL is no longer used, so they will generally remove it from their index.
In contrast to a 301 redirect, a 302 redirect is interpreted by search engines that the redirect is a temporary phenomena, and could change back at any time. Because of this, search engines will not remove the original URL from their index, and will not pass any link juice to the target URL since they expect this situation to be temporary.
This means that if a high-ranking URL moves to a new domain or a new location somewhere else on your site, all of the hard work you've put into getting the first URL ranking well will not be passed on to the new URL location. This can be disastrous for your site's rankings, and therefore is not advised in most situations.