I have never redeemed by 16 KEYs for D2 or LOD. The games do NOT even show up on my account. I have been playing this version for over 10yrs. I download the INSTALL FILES to reload the game. Install FILES require 26 KEY.
You’ll need to redeem your old 16 character alpha-numeric keys for the new 26 character alpha-numeric keys. This process will bind the game to your Blizzard account.
Go here:
https://account.battle.net/overview
Enter the 16 character key for Diablo 2 into the “Redeem a Code” field, then click “Redeem Code”. Do the same for the 16 character LoD key afterwards.
Next, go here:
https://account.battle.net/games
Scroll down to “Classic Games”, you’ll see an entry for both Diablo 2 and Lord of Destruction with the new 26 alpha-numeric keys.
Note: It may take a bit of time for them to show up. If they don’t show up after an hour, try clearing your browser cache and try again, or try using a different browser. If you don’t see them show up after 72 hours, you may need to submit a support ticket.
2 Likes
States the 16 KEY has been already redeemed and GAME does NOT appear in “games”
Error:
This code has already been claimed!
You can only redeem a code once. If you didn’t already claim this code, please make sure you entered it correctly and try again.
You can try submitting a support ticket to see if they can help you.
https://us.battle.net/support/en/help/contact/351/ticket
You can create dummy text files for the dxdiag and msinfo text files they are asking for, since they are not relative to what you’re needing help with. The text files can’t be blank, so just add something to them.
Sad Dizzmal cannot STOP BOTS but sure can stop customers 
There is/was a problem with brute forcing and/or easily guessing the 16 digit keys, which is why they moved to the 26 key system. Unfortunately some people are breaking out their old copies of the game in response to the D2:Resurrected announcement who haven’t played in a long time are now discovering that their keys have been claimed.
That is NOT good. I saw some U-Turds and wanted some nostalgia. I loved this game. DIZZMAL needs to fix this. So I cannot play the Game at all ?
Give the support ticket route a shot. I can’t offer any guarantees on success.
How long does a TICKET last ?
I can’t tell you how long it will be before you get a response. Support ticket response time is highly dependent on various factors, the main one being the sheer volume of incoming support tickets. It could be a few hours, it could also be a few days. I do know however that you WILL get a response.