There are two different reasons an SSL certificate will be in this state:
For Domain Control Validation (DCV), the validation stage applies to every SSL certificate.
When you configure an SSL certificate manually, you will be asked which DCV method to use: email or file.
Based on the selection, an email will be sent or the HTTP file will be returned, allowing you to proceed.
The automatic configuration will use the HTTP file method and attempt to create it at the correct location, which is always the same.
For example, the HTTP file exists at: [http(s)://yourdomain.com]/.well-known/pki-validation/fileauth.txt
For Organization Validation (OV), DigiCert firsts verify that the organization that is requesting a certificate is in good standing.
This may include confirming good standing and active registration in some of the online corporate registries.
It may also include verifying that the organization is not listed in any fraud, phishing, or government restricted entities, or anti-terrorism databases.
DigiCert will also verify the organization's contact and that the organization requesting a certificate is, in fact, the organization to which the certificate will be issued.
If you are still encountering problems and cannot progress your SSL certificate past the pending stage for either validation, please contact our support team to assist you.