Can't boot from cd/dvd or usb

I'm having a problem with my Windows 7 Home Premium 64 bit Acer Desktop PC. Without making any changes to the computer, I turned it on this morning and got the error "Bootmgr is missing" and it gives the option to restart the computer. I have tried to set the boot order for the cd/dvd drive to boot first, with a recovery disc in the drive but it doesn't work. I also tried to boot from a USB flash drive and it doesn't work either. I removed the internal hard drive to get data from it and all the files are on it. I replaced it and checked all connections but still get the Bootmgr is missing error. The cd/dvd drive and USB drive seem to be working, and they do turn on. I would greatly appreciate and help, thanks!

You can't repair WIn7 with a Recovery disk. You'll need the WIn7 installation media or a System Repair Disk to work through Troubleshooting Windows 7 Failure to Start which includes everything that can be done to start it.

I would find the installation media so you have the option to cut your losses and skip to the Clean Reinstall Windows 7 which if you haven't done one yet results in the best possible install of WIn7 and is vastly better than the crappy factory install.

Thanks for the info, hopefully the computer will recognize the cd because when I tried to run partition wizard from cd and another OS from USB, I get the BootMgr is missing message. I was thinking it might not be able to be fixed since it's not recognizing the cd drive or USB.

Failure to boot a disk or other media is almost always a user failure. Where did you get the disk or stick? How is it burned or written? Will it boot correctly in another PC?

If so and you've already tried booting via the BIOS boot order or boot menu key, then take note of the SATA controller settings and reset the bios to defaults. Save changes when exiting.

Otherwise make a new repair disk or installation media following the procedures and step one of Reinstall tutorial below.

Thanks, I will try your suggestions! It was just strange that it suddenly started getting the BootMgr error when I didn't change anything on the computer the night before.

I'm back up and running, thanks for your help, I appreciate it!

Glad to help