Using any plugin results in http 500 error (and only plugins)

try these :
go to dashboard >>updates>> reinstall wordpress

if still does not work
rename: plugins folder to “plugins-old” and create new empty plugin folder

if still does not work
try changing the theme

let me know how it goes

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)