1. A method implemented in a computing device, the method comprising: detecting whether a file on the computing device, created prior to implementation of a data protection policy of an organization, has been written to by a first program that is permitted to access data associated with the organization; adding, based at least on detecting that the file has been written to by the first program, an identifier of the file to a file encryption queue; determining whether any programs on the computing device are currently accessing the file; initiating encryption of the file based at least on determining that no programs on the computing device are currently accessing the file; determining whether access to the file is requested by a second program on the computing device during encryption of the file; aborting encryption of the file based at least on determining that access to the file is requested by the second program during encryption of the file; and allowing the second program to access the file.