Has anyone had to reinstall operating system to get iChat back? Did it work?

Question

We have a three week old Macbook Pro 13 inch. My son installed the Messages Beta. It deleted iChat and now he can't iChat (video etc.) with far away family members because they have iChat and he has Facetime and Messages. He said that during the download it didn't say that it would replace iChat. He said he found out afterward when he went to connect with family.
I tried using the uninstall option on the menu bar of Messages. The "uninstalling" bar gets halfway across and then it hangs, then stops, and we get an error message saying that the software isn't available at this time. I took it to the Genius Bar; same results.
The 32 bit box in "get info" has been unchecked from the beginning; that doesn't seem to help any uninstall of messagesbeta and reinstall of ichat.
I called Apple Care and the rep said that this is a new issue, and after doing some research he recommended I hold the option key down on restart and do a "reinstall". He said he doesn't know if it will reinstall with Messages or iChat however, so I'm checking in here to see if anyone has tried this successfully before I proceed.
(I'm moving his movies, pics and music to my thumbdrive but I think I'll have to do a back up too to be safe.)
Thanks for sharing any insight you might have.
Best regards
Jennifer

Answer 1

Hi,
Message Beta is iChat +
Yes it does replace iChat 6 with Mesages which the About button tells you is version 6.1
IN the Message Menu is the Reinstall iChat option (It is supposed to be kept by some people have reported issues with this)
If you had Buddy Lists in iChat then you can have them in Messages and it will video Chat the same way as it always did.
First check the Messages Menu > Preference > Accounts
As well as the Apple ID (iMessage Account) listed at the top you should still see the iChat Buddy List Accounts.
Check in the Account Info tab that the Box that says "Enable this Account" is ticked.
This will log in the accounts (You may here the sounds that were set in the  Alerts part of the Preference for this action but not see the Buddy lists)
Messages by default turns off the window for the Buddy list. Go to the Window Menu and use the keystrokes listed for each Buddy List.
I have been able to Video to iChat 4 and to iChat 5 and have a 3 way Video Chat between all three versions
In Addition to all the iChat stuff Messages will iMessage
When you are in a Chat with these people then the Video icon will launch FaceTime so you can video their Phone or iPad or Touch (Or to FaceTime on a  Mac)
IF you are in a  Chat with a Buddy it will launch the regular Video Chat window.
Most people that have said their computer says it can't find iChat have not really come back with answers to what they have tried.
One method if you have Time Machine Backs up would be to open the Applications window then use Time Machine and go back until ichat was in the Folder and then "restore"
(From your Post I think that this is not an option for you)
Do you have your Install Disk ?
Apple is moving to the method of having a Restore Area actually on the Hard Drive but I have yet to try things that way.
11:08 PM      Friday; April 13, 2012
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