[Motorola Droid 4] InfiniteIce:
pieeni age

ICS leaks are not fastbootable.AFAIK, unless you just meant that you were trying to fastboot flash to 6.13.219 before flashing to ICS. Either way, here we go.

Go into safestrap, safe mode menu, then disable safe mode, and restart your droid. I am assuming you at least went into safe mode before trying to flash. If so, this is why we love safestrap...makes sure you have a working OS. Let it boot up. Did it work?

If not, don't panic, there is still another solution, even if you didn't safestrap your unmodified OS (just make sure you do this next time!)

If you did backup and safestrap saved you, ignore this block below for now.

[LIST=1]Download [COLOR="Red"]VRZ_XT894_6.5.1-167_DR4-1_M1-219_1FF_01[/COLOR].
You might already have this if that's what you were trying to fastboot to. It's 1.18GB in size.
Download is here: sbf.droid-developers DOT org/cdma_maserati/VRZ_XT894_6.5.1-167_DR4-1_M1-219_1FF_01.xml.zip
(change DOT to . Can't post links yet.)
[*]dl.dropbox DOT com/u/76950573/RSDLite5.7.msi Download RSDLite and install it.
[*]Download the Droid USB drivers:
motorola DOT com/Support/US-EN/Support-Homepage/Software_and_Drivers/USB-and-PC-Charging-Drivers
Install them. [COLOR="SeaGreen"][B]RESTART YOUR COMPUTER.[/B][/COLOR]
[*]Turn your phone off.
Hold the two side volume buttons down together, press and hold the power button down.
Hold all 3 down until you get to the bootloader.
Press volume down to get to "recovery", press volume up to select it.
You'll see a sick looking android/red triangle icon soon.
When you do see him, press both volume buttons down at the same time.[/list]
[*]Volume down to "wipe data/factory reset", power button to select (not volume up this time.)
Confirm, delete everything. When it finishes, select "reboot system", press the power key to enter that choice.
Immediately press both volume keys together after the reboot begins and hold them until you see the bootloader menu again.
[*]Plug your USB cable into your phone and connect it to your computer.
Use volume down to select "AP Fastboot", volume up to confirm the choice.
Open RSDLite on your PC.
Press the "....." icon in the program, browse to and select the 1GB+ VRZ_XT894_6.5.1-167_DR4-1_M1-219_1FF_01 you downloaded earlier.
[*]Click "decompress/start flashing". Now wait for half an hour or so.
I believe there will be several phone restarts near the end, this is normal.
You're now back to stock GB. You no longer have to fastboot to this in order to go forward to ICS.[/list].

Now to get to ICS...

Go here. droidforums DOT net/forum/droid-4-hacks/212307-droid-4-utility-updated.html and download the tool. You don't need anything else but the main tool.

Grab your preferred ICS leak. 6.16.217 is the most recent: droidforums DOT net/forum/droid-4-roms/218610-ics-leak-6-16-217-update-zip-boot-img-crc.html

Flash to 6.13.219 if you didn't just do that.(follow the steps in the CODE block above).

Open the droid 4 tool (.bat file) after extracting from the archive. Plug your phone into the USB. Set it to debug mode. Install safestrap 1.09, root the droid.

Unzip D4 6.16.217.zip. Rename boot.img to ICSFIX.img and move it into the droid 4 utility subfolder named \files\

Copy Blur_Version.6.13.219.XT894.Verizon.en.US.zip (leave it zipped.) to your SDcard.

Go into safestrap and make a backup. Turn on safe mode. Reboot.

Reboot into Bootloader, select AP Fastboot. USB should still be connected and the droid utility open. Select option 16. (Errors might occur. This is fine.) Flash your blur.zip from sdcard. Follow prompts on utility. It will reboot, do some animations. When you see the motorola logo, let it do its thing. Once the moto logo fades out, force a reboot (hold VOL keys & power down.) Now hold vol down and press power, boot to bootloader, and select recovery. Press both power buttons when you see the dead sick android logo. Update from sdcard. Select the zip.

Let it flash. It'll reboot.

Open the droid utility. If you flash to another ICS version, UNINSTALL safestrap 1.09, and then install; the new version 2 one. Make backups. Root your phone. Use the last option on the droid utility to flash between ICS versions.

You cannot use it to flash between something like AOKP or CM9 to a normal ICS version (Yes I actually tried this, lol).

Sorry for wall of text, hopefully this helps you in some way, whether you're still bricked, or still want to go to ICS after fixing your brick.

Resources/relevant threads:

droidforums DOT net/forum/droid-4-roms/218610-ics-leak-6-16-217-update-zip-boot-img-crc.html

droidforums DOT net/forum/droid-4-hacks/212307-droid-4-utility-updated.html

droidforums DOT net/forum/droid-4-roms/209130-how-install-leaked-android-4-0-4-ics-build-droid-4-xt894.html

droidforums DOT net/forum/droid-4-tech-support/206972-how-restore-your-motorola-droid-4-xt894-stock-windows-only.html

droidforums DOT net/forum/droid-4-hacks/200945-safestrap-guide-droid-4-a.html

blog.hash-of-codes DOT com/how-to-safestrap

Read those. It'll be good information for you. I can't post links yet, but it's pretty clear they're not spam and only meant to help somebody out <3