If you think you are only one on Exchange 2003, you are wrong. There are still hundreds of organisations on Exchange 2003 and waiting for the disaster to happen and then migrate! Microsoft discontinued Exchange Server 2003 extended support last year in April 2014 which means that there will be no more security patch support for it or no official support from Microsoft support team for any breakdowns. You would have to purely rely to technical support teams who would have hands on experience with deployment of Exchange Server 2003 which is very hard to find. The scenario will eventually lead to more attacks on Exchange 2003 leading to potential security issues for organizations.
No easy Upgrade to Server 2013 but
The problem with migration or upgrade currently is that this is not a one click upgrade because Microsoft did not create an upgrade path for it and it involves multiple processes. It is recommended that you do transition to to Exchange 2010 and then to Exchange 2013. You’ll have to do at least a double hop migration from 2003 to 2010 to 2013. The other way is to use a third party tool to cross-domain migrations between Exchange Servers. These tools even help to move your users’ mailboxes directly from Exchange 2003 or 2007, to Exchange 2016, 2013 or 2010, without upgrading your existing installation.
Contact us for Exchange 2003 to 2013 Migration support services.