Question: Why can't I import a third-party public SSL/TLS certificate into AWS Certificate Manager (ACM)?

I received an error message when I tried to import a third-party SSL/TLS certificate into AWS Certificate Manager (ACM). Why can't I import my certificate into ACM?Short descriptionI tried to import a third-party SSL/TLS certificate into ACM and I received an error message similar to one of the following:You have reached the maximum number of certificates. Delete certificates that aren't in use, or contact AWS Support to request an increase.The certificate field contains more than one certificate. You can specify only one certificate in this field.Unable to validate certificate chain. The certificate chain must start with the immediate signing certificate, followed by any intermediaries, in that order. The index within the chain of the invalid certificate is 0.Can't validate the certificate with the certificate chain.The private key length isn't supported for key algorithm.The certificate body/chain provided isn't in a valid PEM format, InternalFailure, or Unable to parse certificate. Be sure that the certificate is in PEM format.The private key isn't supported.The certificate that isn't a valid self-signed certificate.

ResolutionFollow the instructions that match the error message.Note:If you receive errors when running AWS Command Line Interface (AWS CLI) commands, make sure that you’re using the most recent version of the AWS CLI.You can import third-party SSL/TLS certificates and services integrated with ACM. Be sure that your certificate meets the Prerequisites for importing certificates."You have reached the maximum number of certificates. Delete certificates that are not in use, or contact AWS Support to request an increase."By default, you can import up to 1000 certificates into ACM, but new AWS accounts might start with a lower limit. If you exceed this limit, request an ACM quota increase.If you receive this error message and you haven't exceeded 1000 certificates for your account, then you might have exceeded the limit for certificates that you can import in a year. By default, you can import two times the value of your account limit per year. For example, if your limit is 100 certificates, then you can import up to 200 certificates per year. This includes certificates that you imported and deleted within the last 365 days. If you reach your limit, contact AWS Support to request a limit increase. For more information, see Quotas in the ACM User Guide."The certificate field contains more than one certificate. You can specify only one certificate in this field."If you are importing a certificate, don't upload the complete certificate chain for the Certificate body field. If you receive a certificate bundle, that bundle might contain the server certificate and the certificate chain from the certificate authority (CA). Separate each file (the certificate, the certificate chain with the intermediate and root certificates, and the private key) that is created at the time of the certificate signing request (CSR) generation from the bundle. Then, change the file to a PEM format, and upload them individually to ACM. To convert a certificate bundle to a PEM format, see Troubleshooting."Unable to validate certificate chain. The certificate chain must start with the immediate signing certificate, followed by any intermediaries in order. The index within the chain of the invalid certificate is: 0"When importing a certificate into ACM, don't include the certificate in the certificate chain. The certificate chain must contain only the intermediate and root certificates. The certificate chain must be in order, starting with the intermediate certificates, and then ending with the root certificate."Could not validate the certificate with the certificate chain."If ACM can't match the certificate to the certificate chain provided, then verify that the certificate chain is associated to your certificate. You might need to contact your certificate provider for further assistance."The private key length <key_length> is not supported for key algorithm."When you create an X.509 certificate or certificate request, you specify the algorithm and the key bit size that must be used to create the private-public key pair. Be sure that your certificate key meets the Prerequisites for importing certificates. If your key does meet the requirements for the key size or algorithm, then ask your certificate provider to re-issue the certificate with a supported key size and algorithm."The certificate body/chain provided is not in a valid PEM format," "InternalFailure," or "Unable to parse certificate. Please ensure the certificate is in PEM format."If the certificate body, private key, or certificate chain isn't in the PEM format, then you must convert the file. If the certificate file doesn't contain the appropriate certificate body, then you must convert the file. To convert a certificate or certificate chain from DER to a PEM format, see Troubleshooting."The private key is not supported."If you import a certificate into ACM using the AWS CLI, then you pass the contents of your certificate files (certificate body, private key, and certificate chain) as a string. You must specify the certificate, the certificate chain, and the private key by their file names preceded by file://. For more information, see import-certificate.Note: Be sure to use the file path file://key.pem for your key and file://certificate.pem for your certificate. If you don't include the file path, then you might receive the following error messages: "The private key is not supported" or "The certificate is not valid.""Provided certificate is not a valid self-signed. Please provide either a valid self-signed certificate or certificate chain."The certificate that you tried to import isn't a self-signed certificate. For self-signed certificates, you must provide both the certificate and its private key. If the certificate is signed by a CA, you must provide the certificate chain, private key, and certificate.

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