I honestly didn't know mods were available for the sims 2 until this week, so this is all new to me. I've read and watched videos on how to install the custom content, but it never seems to work. I extract the files and put them into the "Downloads" folder and custom content is enabled in game. I've been trying to put some pets into the game, not sure if that has something to do with it.

I have the downloadable version of the ultimate edition, not sure if that makes a difference or not.

We have SO MUCH content.

Is your Download folder spelt with a capital D?
Did you enable CC?
Did you make sure the content didn't need a mesh? A mesh is the shape.
If the CC was a recolour you will need CEP.

Can you take a screenshot of where you put it?

https://personalreflections2014.wor...ate-collection/

Did you restart the game after enabling CC? If yes, did you make absolutely sure the box stayed ticked upon re-loading? Sometimes it takes a few tries.

Do you only have (.package) files in your Downloads folder?

There's no use in putting a sims2pack file in your game, as they can't be read as-is by the game. So did you install Sims2pack files with the default installer (the one that automatically pops up), or the "Sims 2 clean installer"?

Do you have the CEP? Without it, some recolors and objects won't show properly.

There are several guides here: http://www.modthesims.info/wiki.php...:Custom_Content
I suggest you have a look at them (partiularly this one and that one, and follow them step by step). If there are any spesific details related to the Ultimate Collection, they're probably covered in the link Jo gave above. If CC still won't show after going through both of them, let us know.

Also can you link us to the content you were trying to install.