Since now your sending the calls to an ICD group you have to set the overflow no answer destination to the pilot # of the VM, set the overflow timer to what you want and program a mailbox 192 to get the no answered calls. Are all your exts analog? If not you can program a message waiting button on digital sets for the 192 mailbox.

Don't know to much about the svm but if you had a TVA you could do some programming and have the message light show on the orginal ext 112

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