The Spireites were confident of announcing one or two new arrivals this week but Cook, while stressing the deals remain close, insists talks remain ongoing with some details still yet to be ironed out.
"We thought at the beginning of the week that we were making very healthy progress in terms of a signing or two. But when you think you're making progress, all of a sudden you can hit a stumbling block very quickly," Cook told the club's official website.
"We're still on with the same ones so the talking goes on and on and on. Our supporters can be rest assured we are very, very close.
"We've got good, realistic targets. I think the likelihood is we're going to sign, before a ball's kicked at the start of the season, a lot more players, hopefully sooner rather than later."