Problem has now been fixed, view last posts for the cause of the problem and the solution. Thanks to everyone who helped. This was driving me crazy...
At first I thought it was the sever I was on or the phpbb script itself, but I was able to narrow the problem down to the style CA_Orbital when I tried the other style prosilver and upon jumping back and forth between these two styles, the problem only exists with the CA_Orbital style.UPDATE: 09/15/2014
People keep mixing up information in this topic, so I'm posting this to get everyone updated on the actual problem and what is actually going on.
No error logs will have this error listed, phpBB works, and log in and log out works! This error is purely an annoying visual glitch, AND IT MUST BE FIXED!!!
In my phpbb forum, anytime someone logs in to the forum, or logs out of the forum, or when I log into the ACP, a page will flash white with just text and no images. Here is video so you can see what it looks like. Flashes White Page W/ Text & No HTML When Logging In/Out
The phpbb.com support forums claim their downloads and all of their styles are fine and that the problem is either a web hosting problem, or the phpbb and/or added styles could have somehow been changed or corrupted during upload and installation. However, turns out many users of the phpbb forum have this problem and do nothing about it, meaning there's nothing that can be done about it with the majority of web hosts out there, which also implies that phpbb has a bug that only shows up on half of the web hosts out there!
The script itself is a combination of php and css, and the problem happens with almost any style added, so the problem is not limited to just one style. This does not happen with prosilver, subsilver2, or any styles that keep their exact layout, but other styles like CA Orbital, Dark FX, Dualcore, and Graand (Red), do show the problem!
The style I'm trying to use is CA_Orbital
To see how CA_Orbital should look and act when logging in and out (without the annoying glitch), you can make a free forum and select the style CA_Orbital on almost any free forum web site.
Clearing the cache in my browser did not solve the problem, and because the style works on other web hosts, I do know it isn't my computer or browser. However, some browsers will not show the problem while other browsers will show the problem. I am currently using Fire Fox to see the problem.
I left my last web host because I had this same problem and they couldn't find a solution to get rid of the problem. I am now on my second web host and they are faster and have better support, but still showing the same problem.
My current Web Host is Linux on a shared Server, with the web space and database on the same server.
I had my Web Host verify I was doing the downloading and uploading and installing of the phpbb and style correctly by having them do it also, and neither of us can do it without the error being present.
If you are having the same problem, post and say so.
If you do not have this problem, pm me and let me know what web host so I can figure out what my web host is doing wrong.
My second step at trouble shooting this problem was to make sure I have the newest version of CA_Orbital, and I do, CA_Orbital 3.0.12
I then glanced at my folders, and everything is in the correct place. My guess is that the problem is located somewhere in /styles/ca_orbital/template/
but there are 105 items in that folder, and I'm not sure where I should begin to look, or exactly what I'm looking for. The only clue I have is that it happens upon logging in and logging out. Can anyone help?