What disks did you have in the box? Cisco uses the MCS servers for various products and they can be ordered preloaded or with the software provided separately. You can also order the "bare metal" versions with no software. So, you would need to check what is stamped on DVDs that came with the server to determine what your actual situation is.
Also, with or without software you will need at least one CUCM node license and DLUs for the phones. Cisco will usually ship what is called a Product Activation Key (PAK) along with the phones and with the software. Assuming you purchased software and the appropriate licenses. Look for a white shipping envelope (cardboard and thin). The PAKs are simply numbers on a sheet of paper. Easily misplaced.
If you find the PAK, then you can go to http://www.cisco.com/go/license and complete the form. You provide the MAC address of the server (stamped on the outside of the chassis) and the PAK codes. In a few hours you will receive an email with the appropriate license files.
So, if you have the software and the license files then it is a matter of booting the server off of the provided disk and following the installation guide for the product you are installing. Search on CCO for "Communications Manager Installation Guide" and look for your target version in the results. There are several pre-requisite items that you may want to have in place, like a NTP server for instance. I highly recommend reading through the install guide before flipping discs.
HTH.
Regards,
Bill
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