[Sprint Samsung Galaxy S III] Undead46:
So I myself had this issue and I was unable to resolve my issue from the discussions on here, but I found something on a YouTube comment that worked for me so I'm here to share.

Basically the trick was to downgrade to an older stock version, then update to LG2 via settings before attempting to install the LG2-to-LG8 update zip.

I do not want credits for any of this if it works for you, I am not the finder of this workaround, nor can I guarantee it will work for you.

Proceed at your own risks!

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So if you're getting this error while trying to manually install the OTA update.zip via stock recovery, follow my instructions.

The Error:

-- Install /sdcard ...
Finding update package...
Opening update package...
Verifying update package...
Installing update...
Verifying current system...
assert failed: apply_patch_check("EMMC:/dev/block/mmcblk0p7:5710080:1a4c067c1e402c5271332f4cec6f0db71826d15a:5714176:1ff968458307c82ac9b6558a090aa6418e619340", "1ff968458307c82ac9b6558a090aa6418e619340", "1a4c067c1e402c5271332f4cec6f0db71826d15a")
E:Error in /tmp/sideload/package.zip
(Status 7)
Installation aborted.

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Files/Programs Needed:

Odin v3.07

LEN Stock Version (Downgrading) - After downloading this, extra contents of zip onto desktop (the .dll isn't needed, just the .tar file) (This is a large file, please plan accordingly to download ~700MB)

I assume you have the Window Drivers needed for SGS3, but if not, download and install accordingly. Download Me

Step 1: Start your Odin.exe as administrator.

Step 2a: Using PDA, load the newly extracted file named "KIES_HOME_L710VPALEN_L710SPRALEN_618049_REV03_user_low_ship.tar" (Screenshot Example)

Step 2b: Leave "Auto Reboot" and "F. Reset Time" checked

Step 3: Power Phone Off (Leave power cord unplugged from computer)

Step 4: Once phone is completely off, boot into Download Mode by holding the Volume Down + Home + Power buttons, and release once you see screen flash with that triangle android symbol.

Step 5: You'll need to press Volume Up to continue from the next screen to go into Download Mode.

Step 6: Now when the screen says "Downloading..." plug in your phone and wait until your Odin.exe has blue "Com:x" box show accordingly.

Step 7: Now just hit "Start" and wait patiently for it to flash the stock LEN ROM. This process will take a while, so don't panic if it's taking a long time.

Step 8: Once that's finished your phone will reboot normally (will reboot twice, just let it go by itself), and now you should be into your stock phone.

Step 9: Now that your phone booted up fine, update your firmware accordingly until you get to LG2. (I believe it will be 2 updates)

--IF YOU WANT TO UPDATE FROM THE OTA UPDATE, JUST KEEP UPDATING UNTIL YOU REACH LG8 AND SKIP THE FOLLOWING STEPS--

Step 10: Once you finally reached LG2, go ahead and download the LG2-to-LG8 update: QBKing77's Download and place it on your SDCard. (It does not need to be renamed)

Step 11: Now power off your phone and boot into stock recovery; hold Volume Up + Home + Power button and release when it flashes the Samsung logo.

Step 12: Once in Stock Recovery, using the volume down button, scroll to "Apply Update from External Storage" and hit your power button.

Step 13: Now scroll to the LG2-to-LG8.zip update and hit your power button and confirm the update.

Step 14: Once that's done, reboot your phone accordingly.

Step 15: Congratulations, if all has gone well, you're now running LG8!

Optional Step 16: Re-root it using QBKing77's Video Guide

*Note: You may need to resynchronize the phone clock to get appropriate time

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