I assume this problem is with your Magix account and not with logging into the forum since you have been able to post here successfully?
Successful log in to your Magix account does depend upon what you originally specified as your email address and password. If you have tried, unsuccessfully, to reset your password that would suggest, I think, that you are not using the same email address as you originally used. So, have you changed your email address? Perhaps the "old" one is no longer active but, if that is the case and you can remember it, you can use it to log in and then go to My Details and then change your registered address to whatever you now use.
If that does not help, I think your only option is to email infoservice@magix.net with as much detail of your account as you can remember and ask for their help in resetting its details to match your current email address.
Attempting to login to my Magix account the page requests a "Secret Question", but I don't have a record of any "Secret Question" that I've set for Magix. No field appears for even entering a response. My username and password both check out, but I cannot login. What might this be?
Your fast response has me speechless. Thank you thank you thank you. I'm attempting to login to www.Magix.com. I click the 'person' icon upper right "account login", and it redirects to https://www.magix.com/us/support/my-service-center/, where I'm presented with the following items
Register
Welcome to the MAGIX Service Center
If you already have a MAGIX login, you can use it to log in. Otherwise you can get a new login here.
I already have a MAGIX login [checked]
Email address: [entered]
Password: [entered]
I have forgotten my password [unchecked]
Security question: <<< This has me completely baffled.
I don´t have a login and want to sign in [unchecked]
To continue, please click on the "Proceed" button below.
I click the "Proceed" button and the page returns an error:
Login incorrect
Unfortunately, your login data was not accepted. Please check your entry and try again.
I can see where the confusion is - the 'Secret question' is a reCaptcha feature which detects that you are a human trying to login - click the check box next to I'm not a robot.
In all the time I have used the Magix service centre, the reCaptcha has always appeared for me at the log on screen.
There must by something system wide on your PC that is preventing the reCaptcha from appearing - maybe a firewall or antivirus program (Clutching at straws I know).
Are you able to try from another PC (maybe even your phone)?