BBC News reports that some of the 6,000 Academy members stated they had suffered trouble with the online method of voting.
Some reported trouble with logging into the website, and others branded the system confusing.
Voting, which had previously been conducted entirely by postal ballot, has now been extended to January 4.
The nominations for the 85th Academy Awards are due to be announced on January 10, and the ceremony itself will take place on February 24 at the Dolby Theatre in Hollywood.
Family Guy and American Dad creator Seth MacFarlane is hosting the event.
Speaking last month, Ted director MacFarlane said that hosting the Academy Awards will not be "Family Guy meets the Oscars".
He also added that he wants to acknowledge the traditional, yet still allow the ceremony to have some "bite".