I can't install Windows 7

Try booting the installer in another PC to confirm it's good up to the step where it sees the HD for install.

If not what always works for me is UltraISO Software To Create Bootable USB Flash Drive.

You can test the hard drive using HD Diagnostic extended CD scan, followed by Disk Check run from the Command Line in System Recovery Options.

If HD checks out the unplug all other HD's and peripherals,

Boot into BIOS setup, reset to defaults, save changes. If an EFI BIOS you'll need to decide if you want UEFI BIOS vs. Legacy BIOS. If UEFI follow these special steps for Install, otherwise enable Legacy BIOS or Compatibility Support Module to proceed with normal install:

Set DVD drive first to boot, HD second, set SATA controller to AHCI, Save changes and Exit.

Then boot into Windows 7 installer DVD or flash stick burned or written using tool and latest ISO for your licensed OS version here. I would use a fresh ISO written with tool in Step 2 as yours is in question.

At first installer screen Press Shift + F10, or enter System Recovery Options to open a Command Box, type:

DISKPART
LIST DISK
SELECT DISK 0 (after confirming Windows 7 target HD #)
CLEAN
CREATE PARTITION PRIMARY
FORMAT FS=NTFS LABEL="WINDOWS 7"
ACTIVE
EXIT
EXIT

Next click Install Now, then Custom install to Clean Install Windows 7 to the partition you created. If it fails then report back at which step and the verbatim error message.

In addition read over these steps to understand the tools and methods which work best to get and maintain a perfect Clean Reinstall - Factory OEM Windows 7. The steps are the same for retail.

After install you can adjust partition size or Create new partitions for data, etc. in Disk Mgmt. You are creating the partition here for the purpose of wiping the HD and marking Active which overcomes certain install failures.

Somehow the ssd was damaged. I had to replace it. Installed Win7.

Thanks for all your help!