permissions are a pain!!!!

How do I get to where I can get rid of or modify the permissions that keep screwing with me when I am trying to set up and access shared files folders and drives in my network? One minute I see the folders and can access some when others give me this crap that I don't have permission to access. Bull!!!! I have everything set to share correctly. Sometimes I can see my group computers, sometimes they are gone. Sometimes when they are there and I try to access them, I get that permission crap.
Where can I go to fix this? Is there software that I can use to "easily" control these permissions? They are really starting to pee me off!!!!

Thank you for any help!!!!

 

Xp Pro sp2 I won't use anything else.

 

So, no one knows how to edit or how to even get a path to where I can modify permissions...????

 

Right-click on the file, choose "sharing and security" or "sharing" (depends on whether you have simple file sharing enabled), and then edit permissions to allow "everyone" "full control"

 

Thanks, I had to undo the simple sharing to access the advanced options.
I appreciate your help!!!!!

 

No problem. Hope you get everything working!