So I have a link in the quick launch that a user cannot see. I have triple checked the permissions and if I give her a direct link, she can access it, but the link doesn't appear for her. It's a custom .net app within an I frame to make it appear to be part of sharepoint.
It's based on an AD group only and other users, like myself, can see this link. I have tried IE, Chrome and Firefox, all in private mode to prevent caching issues. I even created a new link and explicitly added her, did a IIS-reset, cleared all her cookies and cache and still nothing. I have even rebooted the sharepoint app server. It's possible there is a some subtle security issue I don't know about, but I have tried to rule that out.
I stopped inheritance to the page, removed all the groups and added the proper AD security group to the page and the user explicitly, both with full control.
I feel like one of the underlying services on the app server is not working but I don't know where to start troubleshooting that idea. It's confusing for me, because if I make a change it instantly appears for me. I have logged in as this user on my computer and logged in as myself on her computer and the results don't change. This user is working with the direct link for now, but I obviously don't understand something about sharepoint here and it's possible everything is working fine, I just don't get it....