Wake on Line with Acronis backup and recovery

Hello
I have installed acronis console on my server windows 2008.
I have installed acronis agent on a windows 7 computer.
I have installed proxy wake on line on a windows 7 computer.
I would like to start a scheduled backup with Wake on Line because i want to backup during week end.
Its impossible to wake up computers with Acronis.
So i have tested with a free tool to wake up my computer and it's ok.
My free tool wake up convenably my computer.
All my computers are on the same network and sub network.

When i switch on my computer : acronis launch scheduled backup and tell to me that
wake on line is good and backup too.

I dont understand why wake on line with Acronis doesnt work and wake up with a free tool work.

Could you tell me if i can see the result in another log who explain to me why acronis wake on line doesnt work please.

For the moment i try this product , so i have downloaded the free version of Acronis Backup and recovery.
Perharps : it's the reason.

Thank you for your answer.