@JWCalvert : This issue has been discussed in several previous threads. You are out of luck. The Digital Boxes will not boot once you switch to Ignite. They have been disabled.
Had you known, you could have disconnected the box from the RF-coax cable before switching to IgniteTV and connecting the box to a UPS in case of a power failure and you would have been able to watch your recordings, but you're out of luck since you didn't do that
Short answer is yes, however, the 8642 is not worth much and not many people are in need of these older boxes since many are switching to IgniteTV. The 9865 is a much better device and people are only getting about $40-$50. Had you known you may have been able to negotiate a $25 credit from Rogers when you switched to Ignite. Always good to do research before switching rather than after.