Installing lion onto external drive frozen during OSX install

Question

I was trying to install lion into a clean hardrive, using lion recovery.
it's downloaded the first part, and the imac has restarted once and loaded up the "install Mac  OS X " page, it said it was going to take 25mins to install.
It's frozen, about 20% into so install, and now i have the beach ball mouse pointer. and nothing is working.
how can i fix this?

Answer 1

You will need to force quit the installer by shutting down the computer. When you restart look in your Applications folder to see if you still have the Lion installer application. If your do, then I suggest doing the following:
Make Your Own Mountain/Lion Installer
1. After downloading Mountain/Lion you must first save the Install Mac OS X Mountain/
    Lion application. After Mountain/Lion downloads DO NOT click on the Install button.
    Go to your Applications folder and make a copy of the Mountain/Lion installer. Move
    the copy into your Downloads folder. Now you can click on the Install button. You
    must do this because the installer deletes itself automatically when it finishes
    installing.
2. Get a USB flash drive that is at least 8 GBs. Prep this flash drive as follows:
  a. Open Disk Utility in your Utilities folder.
  b. After DU loads select your flash drive (this is the entry with the mfgr.'s ID and size) from the left
      side list. Click on the Partition tab in the DU main window.
  c. Under the Volume Scheme heading set the number of partitions from the drop down menu to one.    
      Set the format type to Mac OS Extended (Journaled.) Click on the Options button, set the
      partition scheme to GUID then click on the OK button. Click on the Partition button and wait until
      the process has completed.
  d. Select the volume you just created (this is the sub-entry under the drive entry) from the left side
      list. Click on the Erase tab in the DU main window.
  e. Set the format type to Mac OS Extended (Journaled.) Click on the Options button, check the
      button for Zero Data and click on OK to return to the Erase window.
  f. Click on the Erase button. The format process can take up to an hour depending upon the flash
     drive size.
3. Use Lion DiskMaker 2.0 to put your installer clone onto the USB flash drive.
Note: The term Mountain/Lion used above means Lion or Mountain Lion.
To reinstall Lion on the external drive:
Partition and format the external drive properly:
1. Open Disk Utility in your Utilities folder.
2. After DU loads select your hard drive (this is the entry with the mfgr.'s ID and size) from the left side list. Click on the Partition tab in the DU main window.
3. Under the Volume Scheme heading set the number of partitions from the drop down menu to one. Click on the Options button, set the partition scheme to GUID then click on the OK button. Set the format type to Mac OS Extended (Journaled.) Click on the Partition button and wait until the process has completed.
4. Select the volume you just created (this is the sub-entry under the drive entry) from the left side list. Click on the Erase tab in the DU main window.
5. Set the format type to Mac OS Extended (Journaled.) Click on the Security button, check the button for Zero Data and click on OK to return to the Erase window.
6. Click on the Erase button. The format process can take up to several hours depending upon the drive size.
Boot from the flash drive you made. Select the external drive as the target, then install Lion.