I bought my imac which had garageband preloaded i had problems with lops so i uninstalled it and bought i fresh copy from itunes
Do you mean "bought from AppStore"? After uninstalling you should have been able to download from the AppStore for free?
Anyway. GarageBand seems to have a problem to remember, that it has installed the additional contents. Perhaps it cannot write the Preferences file. HangTime's "oddball" fix may help:
After GarageBand has completed downloading and installing all of it's extras, remove the GarageBand preferences file and relaunch GarageBand.
- Go to the Finder's menu bar:
- Select Go -> and hold down the ⌥-key, until you see "Library" and double click it.
- Open the folder : ~/Library/Preferences
- Locate the com.apple.garageband.plist file
- Move it to your desktop.
- Relaunch GarageBand.
If still loops are missing, rebuild the loop index: Rebuilding the Loop Index in GarageBand