A "small number" of Scots may not be able to vote in this Thursday's election, the Electoral Commission has admitted.
Because of delays printing and distributing postal ballot papers, a small number of Scots living abroad will not be able to vote in the Scottish parliament election.
Scores of voters have contacted the BBC to complain they have not yet received their postal vote ballot and Aberdeenshire and the Border appear to be most affected. Councils are urging anyone affected to contact them before the polls close.
Andrew O'Neill from the Electoral Commission confirmed to the BBC some people may miss out, but insisted the vast number of postal ballots had been distributed without delay.
"There have been some delays in terms of the distribution of postal votes. Our understanding is the vast majority have been distributed," he said.
Mr O'Neil assured people living in Scotland they would still be able to vote, either by requesting a replacement ballot paper or handing in their paper in person rather than returning it by post.
However, he said people living abroad who have not yet received a ballot paper would probably not be able to vote, adding only a "small number" of people have been affected.
There was an increase in demand for postal ballots this year and ballot producer DRS said this put pressure on its print run. However, it adds it is not responsible for distribution.
Some 1,600 voters in Dumfries and Galloway complained they are still waiting for ballots to arrive. The council reassured Scots they should soon arrive, adding forms were posted last Friday.
The Royal Mail plans to check delivery rooms up until the close of polls on Thursday to ensure ballots posted at the last minute are not missed.
Mr O'Neill said the Electoral Commission had a "duty" to learn lessons from this delay.
This is the latest setback for the postal voting system, after allegations the practice was vulnerable to fraud, prompted by a large increase in the number of applications.