When do you need to Update Deployment Share?
1. When you add/remove network or mass storage-drivers which you want injected into your Windows PE boot image.
2. When you modify Bootstrap.ini
3. When you modify the boot image settings, e.g. scratch space size, custom background image…
So when should you use the option “Completely regenerate the boot images.”?
Well, the answer is that you actually never need to use that option. But sometimes, it could save you some time. If you suddenly realize that it was a mistake to create a boot image containing about 10000000 network drivers, it will be faster to throw away your current boot file and generate a new one instead of mounting the old one and let MDT remove the drivers one by one.