Reinstalled Starcraft 2 (new system), lost my achievements

Solution 1:

Most probably, you have redownloaded a version for a wrong region of the game. EU forums are full of people who accidentally logged in to the Americas.

Recenty, Blizzard has begun preparing to launch Global Play with the release of Heart of the Swarm. They have converted any regional licenses of Starcraft II to global ones. This means you can now download any language version (if you have a non-restricted license) and play in any region with it.

The problem is, until March 12, there is no "Region" button in the UI, so you can still only log in to the region corresponding to your game language.

Fixes:

To the game:

• Go to "Download games" on Battle.net, look for a "Change" link, switch to your language version and redownload the game.
• Wait for March 12, click "Region" on the login screen and log in to the correct region.
• Use a hack to enable region selection in the current version: see this post, look for "regions.xml". Note that mentioning this is forbidden on Battle.net forums.

To the website profile:

http://eu.battle.net/sc2/en/profile/327959/1/Orc/
        \__ server                         \__ realm code

• The website actually should be perfectly fine, you just need to find the right one :) Check if you are logging in to the right Battle.net, and then try to find your profile. I am not sure how to navigate to different realm characters on the same server, but I'd assume it allows to select what character you are logging in with when you do.

Solution 2:

It should be enough to copy an old savegame from C:\Users\%youruser%\Documents\StarCraft II\Accounts\%youraccountnumber%\%someothernumbers%\Saves\Campaign to your new Starcraft II\...\Campaign folder and load it. All the local achievements and campaign progress is loaded from the "last used savegame".

Solution 3:

OK, solved it by first restoring my whole Starcraft II folder (containing the game files) to its previous state (from my old system) and also restoring the Starcraft II folder in "My Documents" to its previous state (old system).

So I basically returned the whole game (game folder and player data) to the state they were on my old system.

Then when I launched the game, it first asked me to wait for 15-20 minutes while the game files were "optimized". Then it installed various patches until the game was up to date. This finally gave me access to my old player profile with all the achievements.

So my guess is that the "optimization" was necessary to be able to continue to use my player data with the latest version of the game.
Since I first installed it in its latest version directly, my player data didn't go through that optimization process and weren't recognized.

Solution 4:

While your solution worked to solve your issue, I think you missed the key to your problem:

the game asked me to create a new character and start a new campaign

Had you not created a new account your campaign progress and achievements would have been listed even with a fresh install.

Achievements and campaign progress are stored on Blizzard's Battle.net servers. In fact, to earn achievements you have to be connected to the internet (they do this to cut down on cheating). To further bolster the case for server side storage you can view my StarCraft 2 achievements gallery.

While I haven't recently performed a repave on my Windows box previous repaves worked without issue. Anecdotally logging into StarCraft 2 from the same Battle.net account on my Mac shows all of my achievements and allows me to continue the campaign. Until a week ago I had never installed StarCraft 2 on this machine (I'm getting excited for HOTS). It is important to note that this does not work for any mid mission save games. Only allowing me to start from missions I've completed.

With all of that said I go back to the fact that you created a new account. Without creating a new account your achievements and campaign progress would have been available as soon as you logged in.

Finally I asked similar questions a few years ago:

• What happens to my campaign progress if I uninstall StarCraft 2?
• Do you keep campaign achievements earned during an unfinished mission in StarCraft 2?

Edit

Your comment that you had not created a new account, threw the premise of what I thought was causing the issue out the window. However, it is disconcerting as the above still holds true: both achievements and campaign progress are maintained on Battle.net servers. If when you logged in with your existing account your campaign and achievements were not listed there is definitely something else at play. Your best bet would be to contact Blizzard Support to work towards a resolution.