The CERN email account will be closed at the same time as your computer account. Therefore you should be able to have access to your emails through http://mmmservices.web.cern.ch/mmmservices/ up to...

The standard procedure is to close your summer student account 2 weeks after the end date of your contract with CERN.
If you require files related to your work at CERN, then you should discuss this...