EWS, which runs 1,500 rail freight services every weekday, has a range of legacy software applications dating from the 1970s.
Matthew Crayton, head of IS infrastructure at EWS, said the application management software from AppSense would reduce the knock-on effects of IT problems with legacy and thin client systems.
"If a train is late it can cost us £50,000 and trains have been late because of problems with IT," he said. "By improving performance we could save about £500,000 a year."
EWS runs centralised IT services from a Doncaster datacentre, using IBM blade servers, Citrix thin-client server software and the Microsoft Windows 2000 operating system.
The company's 200 sites can range from offices with human resources and finance systems to a single-person shunter cabin, which needs access to business and safety-critical software.
Previously, EWS provided access to these applications via desktop PCs. "We were pushing down a full desktop to the end-user and, on quite a few occasions, a desktop took down all the servers because the end-users were playing games or bringing in viruses," said Crayton.
"I have had experience with thin clients and thought that it would suit this environment," he said.
The Citrix and Appsense software has allowed EWS to control which applications can run on the server to prevent IT failures.
The legacy systems included a train scheduling system owned by Network Rail and a roster system that ensures appropriately skilled staff are assigned to each train.
"These systems are not nice to run in Windows, especially not 32-bit Windows," Crayton said. "The efficiency is very low. In the past, we could only get one end-user on the server for some applications because an application would grab all the memory, not because it needed it, but because that was the way it was written."
The Appsense Performance Suite will be rolled out to 2,000 end-users around the UK following a six-month pilot. It limits the demands applications can make on the system memory and processors.
During the first month of the pilot, the applications generated no support calls for IT, an unprecedented development, according to Crayton.
The new system will allow the number of end-users on each server to be increased by 50%.