IPhone 4S Personal HotSpot not appearing in MacBook Pro or iPad2

Question

I've been struggling for a long time detecting my iPhone 4S Personal Hotspot on my MacBook Pro and my iPad2.  Apple support has not been able to resolve the issue.  Sometimes the iPhone would show up; most of the time, not.
Recently, after learning that Siri cannot read Messages to me when I have a passcode in effect, it occurred to me that maybe the Personal Hotspot doesn't show when the phone is locked and/or passcode protected.  I've been doing some testing and I think I've demonstrated to myself that this is true.
Each time I want to connect my MacBook or my iPad to the hotspot, I find I have to slide the lock to open the phone before either piece of equipment will detect it and connect.  I also notice that it takes a long time before the hotspot appears.
With previous smartphones, the hotspot appeared quickly and was always easy to detect as long as it was enabled.
Has anyone else had the same experiences?

Answer 1

I've since resolved this problem - at least so I can cope with it without too much hassle.
You said your phone is unlocked.  Do you have a passcode enabled?
In my experience and testing (Apple support has been useless on this problem), I've narrowed it down to making sure the phone is unlocked and passcode disabled.  Either feature alone will block the WiFi hotspot.  [By the way, I've also learned that Siri is blocked from reading text messages, etc. when the passcode is in effect - even if you are using a Bluetooth device that is already paired with the phone.  Obviously, you must be the owner of the phone if you've pair your device to it.]
I went to my local Apple store on a Genius support visit.  I demonstrated how enabling either feature blocks my iPad's ability to detect the hotspot, and disabling both allows my iPad to see the hotspot.  The guy just said he had never seen that before, and that they are always learning new things.  He didn't do anything to elevate the case to higher level support, like Apple engineering.  I just left the store and that was it.
I've explained this to Apple support more than once and they never seem to be aware of it.  I'm supposed to call to speak with a management level guy, but I haven't remembered to make the call.
So, I walk around with an unsecured phone all the time so I can conveniently access my WiFi hotspot.  And I have to make sure the phone it unlocked until the connection is established so my computer or iPad will find it.  Otherwise, all I can see is everyone else's equipment.
Maybe people don't use the hotspot much.  Apple doesn't seem to care.