Workbench certificates expire after 25 months, at which time an administrator can download a new certificate. To download a new certificate:
Click the arrow next to your account name near the top right and choose Account in the menu.
Select the API tab under the page title.
Click Create Key.
Name your key and assign access to a tool set.
Enter the captcha text.
Confirm and download your key in a ZIP file. You’ll receive the following:
certificate.pem — a client-side SSL certificate signed by Apple Ad Platforms.
private_key.key — a client-side SSL private key.
token.txt— an access token.
Note that the following commands use the publicly available openssl and keyhole utilities. Keytool is obtained through the standard Java distribution.
Convert the PEM certificate to P12 format certificate.
openssl pkcs12 -export -in certificate.pem -inkey private_key.key -out certificate.p12 -name "<NAME>"
Convert the P12-format certificate to a JKS-format certificate.
keytool -v -importkeystore -srckeystore certificate.p12 -srcstoretype PKCS12 -destkeystore certificate.jks -deststoretype JKS