The 19-year-old was charged with uttering death threats and criminal harassment in April 2014.
The charges were laid after Canning said someone posted a malicious message on his YouTube channel in 2013, the year his daughter killed herself. Police said other threats were made on WordPress, an online publishing platform.
The accused was one of two people who were convicted of child pornography charges over a photo of Rehtaeh, who died at age 17 in April 2013. The men cannot be identified because they were minors at the time of the offence in the fall of 2011.
Eric Taylor, the Crown attorney in Tuesday's case, said the forensic results from man's computer don't support the threat charges.
"There was some suspicion but obviously not enough for a conviction," he said outside the courtroom.
As a result, the charges have been stayed and the man entered a peace bond for one year to stay away from Canning and his family.
Taylor says while investigators can track down an IP address associated with an online comment, it's hard to determine who was at the keyboard.
"Unfortunately in this case, as in many cases involving use of the internet and use of social media, it's sometimes difficult to determine who actually posts messages," he said.
Rehtaeh's death made international headlines and prompted new laws cracking down on cyberbullying.
The Parsons family says the girl was sexually assaulted by four boys at a party when she was 15 years old, and then a digital photo of the incident was circulated at school and on social media.