Can't login

Try deleting the cookies and browser cache.

Strange, there shouldn't be other things that affect.

Do you have multiple browsers on the laptop  and have you tried them all?

If you only have one you could try installing another one just to try. 

Windows ?

i mean like operating system

And only MDL gives you problems or other sites too? Always for login

 I have that problem sometimes too. Do you login via google account? If yes, try to login to google directly or into your google acc. on another page and after that use your google account for the MDL login.

I use my gmail account to login, but i can't login with a different email to

Right, so you login with Google+, than it is the same error I expirience sometimes. Did you trty to login to google/ gmail directly? Your MDL account is either bound to you gmail/google account or you have registered directly you cannot huse/have both.