I've checked the groups settings, it is checked so that users are able to edit their own posts, but for some reason they are not able to. Is there another setting I have to change?
No, you just need to be sure that option is enable.
ACP >> Configuration >> Settings >> Posting >> Edit Time Limit
What's that set to?
That is set to 0 for no limit.
EDIT* I started to go through my plugins and found that, Restrict Moderators Editing, was not allowing normal users edit their own posts. Is there a setting for that plugin to make it so they can edit their own posts?
No idea, I've never used that plugin.
Moved to plugin discussion & support.
If they are a moderator, they cannot edit their own posts. Are you using my ported version of DennisTT's mod?? I'll have to get round to fixing it.
Yes, I'm using yours. But the problem is my regular users are not able to edit their posts. I only have 2 super mods and 2 admins (1 admin is me). But when the plugin is active regular users are not able to edit their posts.