Can't create a new boot drive with my data

Have you tried a PRAM reset? Restart while holding down Control+Command+P+R until you hear the boot chime at least twice.

Mac OS X- Gray screen or prohibitory sign appears during startup

It would help for you to tell what you did to "clone" your system. Please outline completely what you did. What make and model of new drive are you trying to use? Is it installed internally or externally? SuperDuper! is not reliable for cloning the newest version of OS X. I would not recommend it. The recommended way is to use Disk Utility. You can clone your existing startup drive by booting to the Recovery HD then running Disk Utility.

well, yes, but he noted that he tried CCC which works great and reliably and tells you if its not so.

I'm wondering about a drive or drive cable problem with the new drive.Note: just because a cable or enclosure works with a spinning drive does nto mean it will work with an SSD, wchih demands much tighter timing and pulse shape control.

Grant

Then he migrated his data which must be corrupted in some way if the cloned system worked fine before migration, but not after it. We also don't know how he prepped the new SSD before using it.

My opinion is that the clone works fine, and he needs to explore what is corrupting things from his migrated data.

with a CCC clone there is no need to migrate data. Its part of the clone, and CCC handles permission changes from one volume to the next

Regardless, Grant, if the original is corrupt then so is the clone no matter how you make it. As for permissions, I don't know if CCC changes the permissions of the source data to the ownership on the target if the two are different. But for this OP that is not the problem.

I don't think we should clutter the OP's topic with a debate over cloning. Please go ahead and give him/her a hand. I've made my remarks earlier. I only replied to you because you addressed me. 😎

You most likely have migrated a corrupted file like a preference, cache, support, etc. You should at least see if you can boot into Safe Mode just to be sure. This is a slow startup and restart because some system cache files and temp files are removed. Then they are recreated on the following startup. After you determine there is no problem in safe mode, reboot normally. If this isn't a fix, then the problem is definitely in your data in your /Home/ folder.

From Apple's article:

Prohibitory symbol

When you see a circle with a slash symbol instead of the Apple logo, it means your Mac couldn't find a valid System Folder to start up from.

If you're using your Mac at a school or business, it might be trying to start from the wrong version of OS X. Contact your IT department for more help.

If this is your personal Mac, try reinstalling OS X by using OS X Recovery.

Be sure you prepped the drive correctly:

1. Boot to your Recovery HD. Restart and after the chime hold down the Command and R keys until the Utility Menu appears.
2. Select Disk Utility from the Utility Menu and click on Continue button.
3. When Disk Utility loads select the drive's (out-dented entry) from the side list.
4. Click on the Partition tab in Disk Utility's main window. A panel will drop down.
5. Set the partition scheme to GUID.
6. Set the Format type to Mac OS Extended (Journaled.)
7. Click on the Apply button, then wait for the Done button to activate.
8. Quit Disk Utility and return to the Utility Menu.
9. Select Reinstall OS X and click on the Continue button.

You can also do the above directly from Apple's network servers:

Restart the computer. Immediately after the chime hold down the Command-Option-Rkeys until a globe appears. The Utility Menu will appear in several minutes, so be patient.

1. Select Disk Utility from the Utility Menu and click on Continue button.
2. When Disk Utility loads select the hard drive (out-dented entry) from the side list.
3. Click on the Partition tab in Disk Utility's main window. A panel will drop down.
4. Set the partition scheme to GUID.
5. Set the Format type to Mac OS Extended (Journaled.)
6. Click on the Apply button, then wait for the Done button to activate.
7. Quit Disk Utility and return to the Utility Menu.
8. Select Reinstall OS X and click on the Continue button.