Windows 7 won't open all any installed applications

to try to answer everyones questions

All programs that came installed on the machine, notepad, defragmenter, disk clean up, etc can open from the startmenu and command prompt. It is the programs that I installed, firefox, malwarebytes, skype, etc. that don't work.

Renaming malwarebytes doesn't work.

I can't open firefox but internet explorer does work, and it does say that I am connected to the internet.

I am on a different computer when I download everything and I move it over to the broken one on a usb stick.

I have run the windows defender scan a total of 3 times.
First time was a full complete scan with 8 hits, which it said that it removed at the end of the scan.
Second was a quick scan after I had restarted the computer and found out that it still was not allowing installed applications to run.
Third was another full scan overnight which came back with no problems.

Safe mode also doesn't work. Booting in safe mode lets me have the same mobility as booting it normally.

Thank you to all for helping me so far, hopefully one suggestion will work.

Also another helpful side note, when I tried to reinstall malwarebytes through internet explorer, I downloads the file but then nothing happens. It completes the download and nothing opens up. I also can't uninstall anything because It won't allow me to open anything that I installed.

Something else I just noticed was that most of the applications in Program Files can open. They all appear to be preinstalled also.
In the Program Files (x86) folder, home to most of the programs I installed, most of them don't work.

I don't know why I have two program files folders, I just had them both when I got the computer from HP. It also looks like all the programs I have installed go to the (x86) folder.
Don't know if this will help just trying to share as much information as possible.

All programs that came installed on the machine, notepad, defragmenter, disk clean up, etc can open from the startmenu and command prompt. It is the programs that I installed, firefox, malwarebytes, skype, etc. that don't work.

Can you start notepad.exe by doubleclicking it in c:\windows ? Still no answer afaik
Program Files (x86) folder is for 32bits applications
Program Files folder is for 64bits applications

Something else I just noticed was that most of the applications in Program Files can open. They all appear to be preinstalled also.
In the Program Files (x86) folder, home to most of the programs I installed, most of them don't work.

Do you run them by doublecliking?

Kaktussoft said:

He told us he can't run exe files. How can he install software?

You can get AV/malware scanners that don't have to be installed in the OS.

To kaktussoft,
Any files I can open open by double clicking on the icon and running them through command prompt. I hope this clears it up.

Will the programs run, if you right click on the icon and select "Run as administrator"?

These may have been covered earlier.

Do you have an AV program?
Is it still (apparently) running?

Does "Windows Defender" still work?
Does it complain if you do a "Full Scan"?

Can you create a new user with Admin rights?
Can that user install/run programs?

gussuk25 said:

To kaktussoft,
Any files I can open open by double clicking on the icon and running them through command prompt. I hope this clears it up.

So ALL exe files run successfully by doubleclick on shortcut?
So ALL exe files run successfully by running from command prompt?