Can't turn of the read-only propertie on my directory

I have a directory that I can't remove the Read-only property.

Its empty but the property is that grey-checked value like I have
multiple selections. But I don't.

I've tried to use both my Power User account and my Administrator
account. It doesn't stay off. Once I reopen the properties window its
checked again.

I'm running XP Pro.

thanks