Southend were relegated out of the English Football League in 2021
Southend United have had their appeal against a 10-point deduction rejected.
The club was docked points in August after failing to clear an HM Revenue & Customs debt before a deadline imposed by the National League.
Southend, who were founded in 1906, felt the punishment was unjust and lodged an appeal.
However, the BBC understands it will stand, leaving Southend bottom of the table despite winning five of their 11 league matches so far this season.
Southend are due back in the High Court on 4 October, having been warned during their last appearance that the club would be wound up if a £275,000 tax bill was not paid.
Owner Ron Martin has been in talks with potential purchasers, although it is thought the timescale makes completion of a full sale highly unlikely before the court date.
There has been speculation that Martin will put Southend into administration - triggering a further points deduction - if he cannot agree a deal to sell the club.
Martin began negotiations with three interested parties following his announcement in March that he was putting the club up for sale.
Earlier this month, two bids from a consortium involving Australian businessman Justin Rees were rejected.
“We remain open to continued negotiations with Mr Martin,” Rees said. “However, it now seems unlikely that any deal can be agreed prior to the 4 October court appearance date.”
Meanwhile, an energy company confirmed last week that it was taking legal action against Southend over unpaid bills.
