EC2 not connecting using Putty

Things to check when trying to connect to an Amazon EC2 instance:

• Security Group: Make sure the security group allows inbound access on the desired ports (eg 80, 22) for the appropriate IP address range (eg 0.0.0.0/0). This solves the majority of problems.

Like below:

• Public IP Address: Check that you're using the correct Public IP address for the instance. If the instance is stopped and started, it might receive a new Public IP address (depending on how it has been configured).
• VPC Configuration: Accessing an EC2 instance that is launched inside a Virtual Private Cloud (VPC) requires:
  • An Internet Gateway
  • A routing table connecting the subnet to the Internet Gateway
  • NACLs (Network ACLS) that permit through-traffic
  
  
  
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