Can I use both an answering machine and SECV voicemail?

Yes, you can use both an answering machine and SECV's voicemail.  
 
To use your answering machine as first priority and SECV voicemail as second we suggest you set your answering machine ring count to be less than the voicemail ring count.  For example, set your answering maching ring count to 3 rings then our voicemail ring count to 4 rings.  If the answer machine does not pick up a call for some reason such as you are already on the phone and ignore call waiting or a power failure in your home, the call will then be routed to your SECV voicemail.

The ring count default for SECV voicemail is 4.  If you would like to change this, please call your local office.