ASG Won't Put Healthy EC2 Instances InService. Stuck in Pending.

Question

I am having trouble getting ASG's to put healthy EC2 instances in service after it starts them. There are no lifecycle hooks. The instances are healthy, passed the EC2 status checks. I can shell into them. But the ASG never moves them from Pending to InService, and eventually it shuts them down.  
  
I tried with a different AMI, subnet, VPC, spot instances, normal ones, and I get the same result. But this only appears to be happening in N. California. Things in N. Virginia seem to be working normally.  
  
Can anyone help resolve this? Thank you!

Answer

I figured it out. When creating a launch config, DON'T check the box labeled "Link to VPC" if you're launching instances INTO a VPC. This is for classic instances that will be linked to a VPC.  
  
It would be nice if there was some sort of error or status message to let the user know about this mismatch.

ASG Won't Put Healthy EC2 Instances InService. Stuck in Pending.

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