A few weeks ago I bought an Acer Aspire E1 522 Notebook with an AMD A6 quad-core processor. I wanted to install a dual boot with Ubuntu, but the Ubuntu installer did not give me the option to "Install alongside Windows". I continued the installation and I lost Windows 8 (a little evil). Then I decided I wanted to start over and do a dual boot with Windows 7. When I rebooted the computer to start Windows 7, the computer gave me an error saying that the security settings did not allow to start the disk.
So I entered the UEFI firmware and I removed the safety lock; however, the computer would not let me install Windows 7. So I changed the BIOS mode in Legacy (I was right) and I finally installed Windows. Then I restarted the computer to install Ubuntu 14.04.1 with the exact same problem starting (I did not check for the next Windows install). Finally I opened the GParted live which gave me an error message saying that probably the GPT partition was erased or corrupted.
What should I do? I only would like to be able to install and use these two operating systems, nothing else. Thank you!