II installed a brush set, and when I checked it, it had an X in each icon, and I could not use it. How can I get rid of the X?

The X means that the corresponding brush tip file is missing.

And how do I get to this corresponding brush tip file?

michaelstolz wrote:And how do I get to this corresponding brush tip file?

That should have come with the brush if you installed it from a different source, in the brushes folder of that brush set to be specific.

I deleted this set and wanted to reinstall it. But it did not. It's an ABR set, but I'd like it. The name is EC Foliage. Thank you

michaelstolz wrote:I deleted this set and wanted to reinstall it. But it did not. It's an ABR set, but I'd like it. The name is EC Foliage. Thank you

ABR files are brush tips:
https://docs.krita.org/Loading_and_Savi ... .2A.ABR.29