This is not possible with Blind Transfer.
It is possible with Consultative Transfer only, In which the original call is put on hold by attendant and a separate call leg is attempted to destination. If destination pickups the call is transfers , if destination do not answer the original call is resumed for further treatment.
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You need to use the Call Forward Busy or Call Forward No Answer settings on the Directory Number to configure this. However, if you set these in a way that it creates a loop ( like A calls B , B doesn't answer and transfers back to A ) then it is not recommended. In a system involving call attendants you can set one of the attendant's settings to send the call to attendant B when it is busy or not available.
Oswaldo, this is the English forum, let's keep it in English as someone else might read this and use the info.
I can't recall what the default is, you can look at it in your client:
Options > Preferences > Advanced >
There should be a no calls and all calls option there, if you want transfer reversal, you need to use all calls, caveat is that since the CTI is used to monitor the transfer and recall the call if the called party doesn't answer, you won't see the actual caller ID of the transferred party.