my iphoto has a question mark over it and now i can't open it. can anyopne help ?

I take it you're referring to iPhoto's presence in the dock? If so, that question mark signals that the dock lost track of iPhoto's location. Just find iPhoto in your Applications folder and drag it to the dock, next to that question mark. Then with this fresh iPhoto icon in the dock, drag the question mark out of it, let go and poof, you're good to go!

If you don't mean the dock, please let us know where you see that question mark.

The question mark is in the dock however iphoto is not in the applications folder either.

Well, iPhoto being MIA still explains the question mark. You may have moved iPhoto inadvertently; did you search for it? If you cannot find it you'll have to reinstall it.

Well... That neatly explains the question mark; the Dock expects iPhoto to be in /Applications.

Next step is to use Spotlight to try to locate iPhoto (assuming you haven't trashed it by accident) and move it back to /Apps, at which point the Dock should see it again.

I can't find it , there is a folder with iphoto , but it cpntains the acknowledgements . Hod do I reinstall.

First you'll need to d/l Pacifist ("Free to try $20.00 to buy").

You can use its search function to find iPhoto, but that can be tricky, because it doesn't always show you precisely what you're looking for at the top of the list.

If you're proficient with OS X, you can work through the hierarchy with which Pacifist presents you and find iPhoto on your own, but if you're uncomfortable with that post back with your version of OS X...maybe tell us whether you're using your install disc or a purchased retail disc, and we'll try to direct you to iPhoto.

using 10.6.4 , 3.2 Ghz intel Core 13 ,

Since you haven't mentioned that you got iPhoto by purchasing the iLife suite of apps I'm assuming that you got it as a bundled app with your Mac. (My mistake... It wouldn't come on a retail install disc.)

I found it at Install Disc 2/Contents of Install Bundled Software.mpkg/Contents of InstallBundledSoftware.mpkg/Contents of iPhoto.mpkg on my MacBook's install discs...here.

Select "Contents of iPhoto.mpkg", as shown, click on "Install," and authenticate if (probably when) asked.

It's time to retire this inaccurate assertion. You may prefer using Pacifist for any and all reinstallations, but doing so is hardly a requirement.

The iLife applications are part of any new Mac's bundled software, and can be reinstalled via the Customize option, as outlined in Mac OS X 10.5.5 and later: Installing optional and bundled software (scroll down to Installing Bundled applications such as iLife (via Applications Install DVD)):

I stand corrected. (Edit: ...about the easiest method of reinstalling iPhoto, anyhow.)

Reminder that dock entries are intelligent aliases, and will easily survive moving or renaming, (though not both at the same time, before being used)

If you've got a ? in the dock it almost always means you deleted it. (second most common is a missing network volume, following a reboot)

If you have more than one user account with Admin access on your computer, it's possible that iPhoto was dragged to that user's account space which would also cause you to not find it. So, if you have other accounts, log into them and look around.