Just had a new hardrive installed, now flashing blue start up screen wont turn on

Question

Everything was fine. I had just picked up my mac, it had been wiped unfortunately. I got everything reinstalled, happy as a clam. Stupidly I didnt have my back up yet from the store, external drive. I was messing around with my customization, I installed opaque menubar, a custom log in screen and then I went into my system and replaced sart.bin file with one to replace my apple symbol with the classic rainbow. Unfortunately the file I replaced it with is probably not right. It ended in a c something. Instantly after I hit restart, it went to the blue screen with the loading symbol, flashing back and forth between blue and green blue. Im wondering if it has to do with the login screen change of appearance, the sartfile or if that when I picked up my mac and the apple genius guy turned it on, it made a loud beep and he had to take it back and take out the memory. What would cause this? When I go to utilities to verify and repair, it tells me nothing is wrong with my disk. Which makes me scared because I already spent 300 dollars to repair this computer and just reinstalled everything. I was in tears over the aggrivation. If anyone can shed some light on this and some clue what this is a sign of.
Again. On start up, it shows the white screen, apple symbol, loads then goes to the blue screen and flashes two shades of blue with a loading symbol. Any feedback will help me immensly

Answer 1

What exacty happnes when you try to startup?
Wha installed the HD?
What model MacBook Pro?
It it has Internet Recovery then boot into Recovey
OS X: About OS X Recovery
There you can use disk utility and reinstall the OS. Otherwise y owill have to boot for an Install Disk
BTW, this is the Mac Pro Desktop forum