I know there are already guides out there but people are still making threads and asking how to fix this error.
1. Un-install the game and remove the DBO folder.
2. Re-install the game.
3. Open the launcher and wait until the patch hits 0416. The number in the parenthesis is the patch number. Once it finishes 0416 then close the launcher. If it patches all the way to 0419 then go back to step 1 and restart the process. Do not re-open the launcher after it finishes 0416 and you close it!
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4. Open your DBO folder and find DBO.exe. If you have extensions hidden then it should just be called DBO. If you can't find it then open the target location of your launcher and you should be able to find the file.
5. Run DBO.exe(Dbo) as admin.
This is tested and it does fix the solution. If it still doesn't work for you then you did something wrong and do it again starting from step 1.
If this doesn't work then you have to wait until Wasabii fixes the problem.