David Crichton had told the court he typed in details and selected a ‘kill’ option costing 4.25 bitcoin, which was worth £3,800 $4,975, €4,279 at the time, as a mental exercise to clear his head.
According to newspaper the Bournemouth Echo, which first broke the story, no money exchanged hands and Crichton told jurors he believed the site was a scam.
However, the 64-year-old was convicted of three counts of sending malicious messages to his former adviser, who he had held responsible for a £300,000 loss.
The court heard Crichton blamed the adviser despite not following his recommendations and consequently triggering a tax bill.
The doctor has been released on bail pending a date for sentencing.