I have 2 TiVO HD units connected via wireless net. For years have been able to transfer program files between units without problems. Recently, have been unable to transfer. Transfer starts, will go for a while, then stops before finishing. The program is gone from the destination unit as if the transfer was never started. No failure indicated in last transfer from diagnostics, just that a transfer took place, but the time is short. Nothing in the network has changed, signal strength still OK. Failure happens with or without recording activity on one or both units. I still need to do more experiments to see if it occurs in both directions, program size, etc.