BootManager (BootMGR) is missing?

I have a toshiba satellite laptop and i used a toshiba recovery disk to fix a couple drivers that were messed up but i didnt realize that the second recovry disk was missing so once the 1st disk was finsh being installed i canceled the installation concluding that some programs may hav been erased and when i restarted my laptop an error message popped up "bootmgr missing press ctrl atl and del to restart",,if i get the 2nd recovry disk can i fix this problem, if so how.? Since my computer wont boot up how do i get the disk to start up ( F1 or F12) any answers?