Ritchie - who is on loan at Swindon - would have been a free agent if the south-coast club had closed down but after Steve Cotterill's men exited administration he feels the future is bright for Pompey.
"I've been seeing what's going on but just had to take it as it came a day at a time," he told the Swindon Gazette and Herald.
"Obviously I'm still paid by them, so it was a bit of a shock to hear that they could be going out of business, but we had a game as well so I just had to try and concentrate on Leyton Orient and let whatever was going to happen, happen.
"I was in the same position as everyone else and didn't know what was going on. Hopefully the club can push on now and get things sorted."