Open the ZIP file containing your certificate and copy your_domain_name.cer to the Office Communications Server where you generated the CSR.
1. On the server, click Start, then Programs, followed by Administrative Tools, and then click the Office Communications Server 2007.
2. Expand the snap-in until you find the Enterprise Edition Server.
3. Right-click on the Office Communications Server where the CSR was generated previously, and click Certificates.
4. Click Next and then chose to Process the pending request and install the certificate.
5. Browse to your_domain_name.cer and click Next. The will install the certificate You can view the certificate and close the certificate wizard.
Your SSL Certificate is now installed a ready to use.