Many times people are reaching VPC limits not because they're running other VPCs on AWS, but because they've already deployed several times (AWS allows five VPCs per region). This lets people know they can simply delete their old VPCs instead of contacting AWS support.
Algo builds a [Cloudformation](https://aws.amazon.com/cloudformation/) template to deploy to AWS. You can find the entire contents of the Cloudformation template in `configs/algo.yml`. In order to troubleshoot this issue, login to the AWS console, go to the Cloudformation service, find the failed deployment, click the events tab, and find the corresponding "CREATE_FAILED" events. Note that all AWS resources created by Algo are tagged with `Environment => Algo` for easy identification.
In many cases, failed deployments are the result of [service limits](http://docs.aws.amazon.com/general/latest/gr/aws_service_limits.html) being reached, such as "CREATE_FAILED AWS::EC2::VPC VPC The maximum number of VPCs has been reached." In these cases, you must [contact AWS support](https://console.aws.amazon.com/support/home?region=us-east-1#/case/create?issueType=service-limit-increase&limitType=service-code-direct-connect) to increase the limits on your account.
In many cases, failed deployments are the result of [service limits](http://docs.aws.amazon.com/general/latest/gr/aws_service_limits.html) being reached, such as "CREATE_FAILED AWS::EC2::VPC VPC The maximum number of VPCs has been reached." In these cases, you must either [delete the VPCs from previous deployments](https://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/working-with-vpcs.html#VPC_Deleting), or [contact AWS support](https://console.aws.amazon.com/support/home?region=us-east-1#/case/create?issueType=service-limit-increase&limitType=service-code-direct-connect) to increase the limits on your account.