Black solid square keep popping up on my screen

How big is this black square? Is it like 1/4 to 1/2 the size of the screen? If so, you probably have Closed-Captioning turned on, and turned on to TEXT mode. Either change it to CC1, or else turn it off, and your black square will go away!

It is most likely related to the Closed Captioning option on your TV. Go into settings and make sure that CC is turned off, or make sure it's set to CC1. What you are probably seeing is the "text" option included in the CC options.

ok...
1.take off battery cover, remove battery, memory card and sim card
2. remove the five screws on the back... two at the bottom, two in the middle and one on the mid top right and take off this cover, remember! keep the screws safe
3. slide the phone up and take out the two screws on the left and right paralel with the battery tabs then remove the two screws ether side of the camera...they might be covered by rubber coverings, these pop out easily
4.now you can prise the top of the screen off with a small flat headed screwdriver
THERE ARE TWO OPTIONS HERE, IF THE REPLACEMENT SCREEN HAS NO RIBBON CABBLE ATTACHED THEN FOLLOW FROM FIVE, IF IT HAS ONE CONNECTED THEN FOLLOW FROM
5. its conected to a ribbon cable, remove the tape and slide out the cabble from the screen.
6. now take out the screen PCB from the plastic casing and replace it with your new one and put the ribbon cable in and clip it back together, now reverse stages 3 to 1 to put it back together.
7. if the ribbon cable is attached now you must look at the PCB board on the back for a square copper line, on the left of this there is a big black square just smaller than the copper square, prise this off with your finger nails, keeping it to the side take the PCB up about 2mm and then fold the bottom of it to revele it is conected to a ribbon cable by a bigger version of the black square so prise this off and take the PCB and put it safely to one side.
8. look on the front of the phone under the top bit of the screen, there should be a semi circle in the plastic with a black circle in the top of it, use your nail or a flat headed screwdriver to pop it to the other side of the semi circle, now the slider should go past what it used to o you can slide it up to when you can see the ribbon cable go down through the phone, now push the black square end through and you should be able to slide the whole front off.
9. replace the screen by taking the screen PCB out and repacing it, then thread the ribbon cable back through and slide the front on while making sure the back circle goes into the semi circle and to the top side of it, then thread the black square through the phone to the front and clip the phone front back on.
10. snap the black square back on to the back Circuit then put the circuit back into the phone and snap the small black square back on then go from stages 3 to 1 to put it back together.
this should be fairly easy to do for most people.

the light tunnel is either collapsing and blocking the light going through it (and needs replacement) or the vertical/hoizontal adjustment of the tunnel. if you take the lamp out and move the colorwheel (with a pencil eraser) to the clear section, you should be able to see a square through it. if part of the square is blocking the middle, the tunnel needs replacing.

by the way, on some projectors the light tunnel is called an integrator rod.

in menu, turn off cc-closed caption

Mark, Stupid me did not buy the additional warranty that I could have.. I have bought warranty on every television I have ever bought, and never once did I even need it. Even til this moment I still have the reg tv's and they all work great....On this flat screen, it isn't always this black squares pop up. I might also add, they do not stay in one spot. one moment it will be flashing at the bottom, the next it might be at the top or in the middle...then it waont do anything for weeks....any Ideals??????thanks for trying to help[

hmmm...the black square syndrome..sounds like the picture in picture settings are unhappy..check those, to see if maybe it's on some sort of timer, and accessing a non channel(which might explain the black square).

shut off the close caption, the caption is is in text mode and needs to be changed to CC1. the remote may have a cc button on it push it until cc is off.

He, he. Somebody activated the subtitle mode on the remote. Desactivate the CC mode on your menu and it'll go away or at least if you want CC put it in CC1 Text1

Shut off the closed captioning and your problem will be gone.

I’m happy to help further over the phone at https://www.6ya.com/expert/dewayne_4a10eab6caecdb92