[Solution] for the re-install bug

Aright, as many of you noticed, you will get an "unknown error" message, after you tried to reinstall D3 and you wont be able to reinstall it again.
Since the blues are busy with ...whatever, I fixed the stuff myself and wrote the solution down for you guys.

Sidenotes: System Win7, DX11, Radeon5770HD gfx, firefox

I solved this problem by doing the following:

Step 1: Update your graphic drivers (in any case this is never a mistake)
- google for your drivers and dont skip this
Step 1.5: Download a fresh client from your battle.net account
Step 2: If you try to install it and get the error, check options and reset game preferences
Step 3: Make sure you run the system as admin - IF you are a windows 7 user do the following
-> go to system preferences -> useraccounts -> settings
-> drag the ruler to the 2nd spot from above
Step 4: push the windows key and enter "regedit" in the search spot
-> HK_CURRENT_USER->SOFTWARE->BLIZZARD ENTERTAINTMENT->BATTLE.NET
-> delete D3

REBOOT

Step 4.5: Disable Antivir/Firewall
Step 5: Now try to install again BUT DONT USE YOUR BROWSER (srsly I have no idea why it bugs for me, but it wont work if you try running it by the download tab via browser) - just manually use the .exe

Step 6: Launcher should install properly now - let it finish
Step 7: Go to your systemprefereces in windows and unseraccount settings again
-> drag the ruler to the lowest and restart (this prevents in many cases the error at the login)

Step 8: Start the game and !@#$ing enjoy again, bros&sisters
Step 9: gimme a hug and politely ask blizzard to fix the serverside errorcodes (24000 etc)

Have a nice day

If you get the Error 3 code do the following and relaunch the program not as an Admin:

c:\ProgramData\Blizzard Entertainment\Battle.net\Cache\cache.db

delete the cache