If someone you went to school with tried to contact you 20, 30, 40 or more year later...

Would you be suspicious? I don't know how I'd react as I'm not into school re-unions and successfully avoided the 10, 20 and 30 year high school yr 12 re-unions.

I haven't crossed paths (knowingly) with anyone I went to school with since having my adult kids in the late 1990's and early 2000's, and never kept in touch with anyone from those school times (high school for me was 1981 to 1986).