Iphoto yellow triangle with exclamation point...

Are you able to send even if you get the triangle warning and do the photos arrive at the destination?

Try this: launch iPhoto with the Option key held down and create a new, test library. Import some photos and check to see if the same problem persists. If it doen't persist in the text library the problem lies with your existing library. If that's the case make a temporary, backup copy (if you don't already have a backup copy) of your library and apply the three fixes in order as necessary.

Fix #1

1 - delete the iPhoto preference file, com.apple.iPhoto.plist, that resides in your HD/User/Home()/ Library/Preferences folder.

2 - delete iPhoto's cache file, Cache.db, that is located in your HD/User/Home()/Library /Caches/com.apple.iPhoto folder.

3 - launch iPhoto and try again.

NOTE: If you're moved your library from its default location in your Home/Pictures folder you will have to point iPhoto to its new location when you next open iPhoto by holding down the Option key when launching iPhoto. You'll also have to reset the iPhoto's various preferences.

Fix #2

Launch iPhoto with the Command+Option keys held down and rebuild the library.

Select the options identified in the screenshot.

Fix #3

Using iPhoto Library Manager to Rebuild Your iPhoto Library

Note: This creates a new library based on the LIbraryData.xml file in the library and will recover Events, Albums, keywords, titles and comments but not books, calendars or slideshows. The original library will be left untouched for further attempts at fixing the problem or in case the rebuilt library is not satisfactory.

If you get the same problem with the test library reinstalling iPhoto is indicated. To do so you'll have to delete the current application and all files with "iPhoto" in the file name with either a .PKG or .BOM extension that reside in the HD/Library/Receipts folder and from the /var/db/receipts/ folder,

Click to view full size

Then install iPhoto from the disk it came on originally and appy all required updaters.

In other iPhoto items like books, calendars, etc. the yellow triangle is an indication that the photo doesn't meet the minimum size standard that iPhoto has set for printing. What it means for an email I have no idea. Haven't heard of this particular problem before. Try sending it to yourself and check the resulting photo file to see what you get.

OT