we are experiencing issues with end-users trying to log in to the website and cannot.
they receive the error "An unspecified error occurred"
is there anything that can be done to resolve this I have 250 users affected.
Can you check logs for specific error of Magento? var/log folder or any reports in var/report folder.
Apart from that you can just check by printing error message.
vendor/magento/module-customer/Controller/Account/LoginPost.php and put these lines
$message = $e->getMessage();
just before lines-
__('An unspecified error occurred. Please contact us for assistance.')