Irrelevant to your solution, but it should be noted that you should never be using the Default Admin account. Hackers tend to target that account first as it is default on Windows Operating Systems. Newer versions of Window's includes the account, but have it default to a disabled state.
It is good practice to do your daily computing activities on a Non-Administrator account and only login into an Administrator account that is not the Default Account when you need to make system-wide changes.
Also, what language is your Windows Operating System using? It would be nice to run the screenshot through Google Image Translator and see what the error message actually says.