The actor, who plays Adam Barlow, lasted 3 years in the role before moving on to other projects, including Celebrity Big Brother and Beaver Falls.
The 31-year-old has now revealed that he struggled to find his place on the soap when he first started.
"The trouble 10 years ago was that I was on the periphery and when the character was not that involved, it was hard to get momentum going," Samuel told The Scottish Sun.
Samuel Robertson explained he felt like "a spare part" on Corrie in 2004
He confessed the show "feels different" this time around
It was my fear again but it couldn't be more different this time
He continued: "I don't think myself or the show's writers or producers had any idea of who this character was.
"I said to the producers and casting department that I felt like bit of a spare part the first time around.
"It was my fear again but it couldn't be more different this time," the actor confessed.
Samuel added that he is now "having fun" playing devious Adam since returning to the soap last year.
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"I'm playing him as charming as possible because at first I was unsure whether I wanted to play a character like that. It's been fun, I'm enjoying it, I feel like I'm creating a character now which is great fun for me.
"I've been back a year now and it's effectively a brand new character and production team.
"It feels like a brand new job, and the first few months were just finding my feet. It's been a pleasure for me as the people I'm working with are really well established, big characters in the show, so it's good fun and really satisfying," he said.