The injury has plagued left-sided player Daniels throughout the season, limiting him to just three league starts.
But Daniels, who has operated a left wing-back role but can play as a traditional left winger, felt the problem again after returning from the sidelines as a substitute in the 3-0 defeat at Chester on Saturday.
“Brendon has felt something again, so we won’t be seeing him for a while unfortunately,” said boss Cowan.
“He’s come on the pitch, declared himself fit, we’d done a lot of work with him.
“But for whatever reason it’s another part of his hamstring, it’s a little bit out of our control really.
“We’ve got great (physio) guys in Aaron (Lambley) and he does a lot of extra stuff at Love2Stay in Shrewsbury. We’ve gone above and beyond to get it right.
“But for whatever reason the hamstring won’t do as it’s asked.
“We’re really disappointed not to have such a big player available again. That’s probably my most disappointing part, as well as losing.”
Telford did have powerful striker Jason Oswell back from a hamstring injury.
Cowan added: “Ossy had a good 20 or 25 minutes under his belt and is a big player for us and will play a big part moving forward.”
The Bucks were also boosted as versatile midfielder Henry Cowans took another step forward in his recovery from a quad problem.
Cowans, who was also played right wing-back this term, was out running ahead of the clash at Chester.
Cowan’s Bucks have slipped to 12th after back-to-back defeats over the Christmas period, but remain just three points from fifth in a congested National League North table, albeit having played more than many of their rivals.
The tough tests continue with fourth-placed AFC Fylde, relegated from the National League last season, the visitors to the New Bucks Head on Saturday.