MT4 Software help needed

I am new to MT4

Hope I do not bother, but I experience a MT4 Software Problem:

I have downloaded the Avafx MT4 Demo Version on my PC

Now I have applied for a real Account, I deleted the "old" Version and downloaded a "new" Version ( I thought so ) - and can not logging into my Real Account

It appears, that my "old" loggin ( Demo ) Datas are "printed" onto my PC

Excuse, if my Explanation is a bit unclear or unprofessional - but this is what I experience

Can anybody help me or give me a Clue - like how to 100% delete the "old" Datas and MT4 Software, so I could start downloading my "real" Version and loggin with my Account Details?

Hi,
If you just want to 'Log In' with your live account.
Open Metatrader and go to "File" in the top left corner.
In the drop down box click 'Login'
When the 'Login' box opens, input your new account number, the password you have been given and if required the server type (not the demo server for a live account).
Click save, and you should login to your new account.

thank you very much for your time to answer to my thread

but as I told, I can not give in my real account login datas

it appears a "1" - printed in and unable to delete

I believe, the only solution will be to delete the whole MT4 software -
but I am unable to do so

any further ideas, how I should proceed?

Copy your indicators you require from the existing MT4. Save them to a folder on your desktop. Go to the MT4 folder and use the 'uninstall.exe' to remove the current MT4.
Try downloading another instance of MT4.
Create a folder in your 'C' drive with a different name to the current folder your MT4 is in, and save the 'new' MT4 to that folder.
Run the MT4 and when you get the 'open new account' box cancel that, and then input your 'live' account details.

Hope this helps