Posts and pages repeat themselves 4 times in the loop

Problems similar to this are many times caused by a plugin.

If you look at the actual wp_posts table do you see each post just one time? If so, then maybe plugin(s) need to be de-activated.

See below for today. I had posts doubling.

Quick checks.

Does this happen when you switch to another theme.
If it doesn’t show up in another theme, then (I think) the problem may be in the index file of your theme.

Look for and identify The_LOOP. If you don’t know what it is, see the Codex.

Then look for anything within The_LOOP that occurs more than once. To check, use comments; <!-- before what looks like something extra, and --> after just that line.
Then hit the button to update your code, and hit the <view site>.

If that worked, you should be seeing either single or double. If single, then you are fine. If you are seeing double, there might be another extra line of code in The_LOOP (particularly “content” lines in PHP code).

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If those things don’t work, then MichaelH has the right suggestion, about plugins.
To troubleshoot plugins, take them one by one.
Do this:
Deactivate the plugin
Check <view site> if your blog is still in quadruplicate.
If it is, reactivate the plugin.
Repeat until you either find the plugin that is causing problems and deactivate it, or you run out of plugins.

Just in case it’s more than one plugin, note where you stopped.

It happens to me in every theme, so I will check plugin by plugin if any of them is making conflicts and I will let you know.

Thanks so much,

Antonio

I have checked everything and I have found the problem. I don’t know the reason, but I am able to fix it.

I installed the plugin Simple Tagging after a few months of runnin my blog. Since categories and tags work differently, the plugin said if I wanted all categories to be transformed in tags. I said Yes.

The problem is that the posts that had, for example, categories: “Computers” and “Internet”, after the plugin was activated, all the posts had their respective categories AND also the same categories but as tags.

Something must have confused the loop and it repeated the post or page as many times as number of categories (this certainly sounds as a bad horror movie). Editing post by post and erasing categories fixes this problem.

Thanks so much for your help, guys. MichaelH, petersig, thanks so much, really.