UBB.threads PHP Forum Software Community Forums UBB.threads Version 7/8 Support Images not uploading

Everything has been working fine until recently. I don't know of any changes I've made that would cause this, but here's what's happening all of the sudden.

I have a gallery forum.
I try to post "New Image"
I go to Image Manager and Choose and Image, the "Add File".
The image file name shows up at the top of the file manage like it should.
I click "Done adding files"
Then I submit my post but the image shows up as a broken image
When I use filezilla to look at the gallery directory where it says the image is stored the image is not there.

Seems like the image is not uploading.
Any idea why this might be happening? I didn't change anything.

UPDATE: Well, I solved the problem. I ran the Permissions test in CP and found that many of my folders' permissions failed. I have updated them all to pass the check and now all is back to normal. What is weird is, I don't know why it was working fine before, then all of the sudden decided to stop working. I didn't change anything or any file permissions myself intentionally.