Black Text On A White Background (Previous Setting). How, Please ?

[Robert11]

Hello,

Old age problem again, but have really tried (for a long time)

The colors on my opening screen are fine.

But, I cannot go back to what I normally had.
Black text on a white background for eMail, etc.

Have tried most everything I can think of, but won't revert
to what I had before.

Can someone, please, tell me the very "exact" steps to follow to
have black text on a white background for Mail, etc. ?

Would be most appreciative.

Thanks,
Bob