Papers were due to be sent out yesterday to the crofting community on the Pairc Estate on Lewis in a move which was expected to bring an end to the most protracted and acrimonious buyout of its kind in the last 20 years.
It came about after terms of a voluntary transfer of the estate to the community were negotiated between the Pairc Trust and landowner Barry Lomas, who had originally been unwilling to sell.
But unless the setback can be resolved, the issue could yet be destined for the courts as Scotland's first hostile community buyout.
Angus McDowall, Chairman of Pairc Trust, said: "We regret that it has not been possible to finalise the documentation by the due date, and we have no option but to call off the ballot."
The Pairc Trust had made clear it was willing to pursue the first "hostile" buyout under the Scottish Parliament's land reform laws, in which the landowner was unwilling to sell.
Mr Lomas, of Leamington Spa, mounted a legal challenge in the Court of Session. However three judge dismissed his appeal.
But after 11 years it looked as though residents in the South Lochs area of the island were finally going to buy the 26,800-acre estate for an agreed price of £500,000 and the ballot was organised. The result was expected to give final community endorsement to the plan.
Mr McDowall said discussions were ongoing with the estate and if they could be satisfactorily resolved in the next few weeks, another ballot would be arranged.
But he said: "If it is not possible to resolve the issues, we will have to abandon the Amicable Estate Transfer route and rely on the Courts to determine the outcome of our applications to buy the Estate under Part Three of the Land Reform (Scotland) Act."
Mr Lomas said: "A great deal of work has gone into this already, so I don't want to comment at this stage."