Possible causes of user not able to login to an application

• Incorrect username or password

• Account locked or disabled

• Expired password

• Network connectivity issues

• Application server down

• Incorrect permissio...read more

User is lock

Usermod -L and user lock command

Communication between the Application & database is not happening.Invalid Credentials.Application stuck due to Memory/CPU Full utilization.

1) server is down and not accepting any login request(web server)

2) login Credentials are not valid

3) user authorization is not given for that user

4)multiple signing attempt then root block thart u...read more

may be /usr is ful that's why user not able to login 

may be user not excited in the appliction

may be user dont have the permission for login.

User is restrict in /etc/ssh/sshd_config file

any relevant entries under /var/log/secure or /var/log/auth.log user not able to login appliction