Hot/GRD. Reverse and ???

I have been pursuing a home electrical problem without success and wondered if anyone has some tips. The ceiling lights and outlets in two rooms (bed room and foyer) suddenly stopped working. There has been no changes to the house since it was built 30 years ago. I read the previous DIY Forum tips on this topic and went looking for a loose connection. I even went to the extent of changing out all the wall outlets, wall switches and even the ceiling lights in the two rooms to no avail, my problem remains. I screwed all wires in on the new hardware to avoid the chance of a loose connection with the stab-ins. If this is a loose connection culprit I haven't found it yet. Now for the twist. Depending on the position (on / off) of the either the bedroom or foyer wall switches the tester reads either a Hot/Grd Reverse or a solid amber light and a dim amber light of my tester for all outlets in the rooms. My tester is a GB Electrical GRT 500 model and the correct circuit indicator is when both ambers are bright. In all configurations of switch positions and tester light patterns I have no power.

Help,
Bob

hot and ground are reverse indicate to me some has termated in a light fixture or out let. termated line could be comming from another room thats working adj room ceiling light. sounds like a do it selfer just wired to the closes source and did not follow color codes (wiring color).so look in a room that you thing who ever though and look in the ceiling light or closes outlet. 30yrs ago their were no wiring standards and laws this one got away.supprise house inspector did not catch that when you went to buy the house.

also turn light switches on in other rooms it may be tie into another light switch if so thats a no no some was dumb.

There is another room in this situation. That room feeds off of the same breaker of the two rooms that power has stopped on. This other room remains with power. That is where I'll look next for a loose connection.
Thanks for the reply.

I AM NOT A PRO BE VERY CAUTIOUS WHEN DOING ELECTRICAL WORK ----Do at your own risk---

Thought I share my resolution since I had same problem this weekend.

The power in my sons room/garage/laundry room suddenly turned off sat night. Nothing unusual going on in the house or out.

Circuit was not tripped (in off position). I turned all breakers off then on. Power still not on. Went to local box store and got multi meter, non contact voltage detector, and circuit tester. My plan was to check from breaker in. (A plan I shoud of stuck too). Got back home tested all breakers (used multi-meter) all passed current. Next used voltage detecter in sons room, tested positive for voltage, next i plugged in circuit tester, tester indicated hot&grd reveresed. I know a gremlin didn't go and rewire my sons room so did some research on google and all things pointed to open neutral. Here is where I messed up..I assumed that it had to be a socket so I went out and bought 5 sockets and replaced them all (house had stab in i bought screwin was told they were better). Still nothing.

After scratching my head I decided to go to original plan.

Followed circuit from breaker in using voltage detecter I was able to isolate the sockets and swithces. I noticed that the garage outside light worked and it was on same circuit. That told me that the open nuetral was probably that switch or right after. Checked switch and tightened twist cap used on nuetral wire, still nothing next on circuit was attic light (which was added by someone after the house was built.) Removed switch and tightened nuetral wire twist cap connection. Tested and all worked.

If I had started and stuck with my plan I would have saved a few hours and a few dollars.

I hope this saves someone time. I'll get more detailed for those who ask.