According to the Electoral Law, Afghan refugees and diplomats retain the right to participate in elections, if possible for the Independent Election Commission to accommodate. However, due to its cost and scale of operations required, the IEC is not yet able to provide this service to out-of-country voters.
Source :
IEC Factsheet, Frequently Asked Questions: Voting in the 2014 Elections, http://www.iec.org.af/2012-05-29-07-06-38/faq