Please find code below. PSTFile object is not releasing reference of a file. I have to delete file once mails from PST files are read and stored in DB. PSTFile pstFile = new PSTFile(tempFile); processFolder(pstFile.getRootFolder(), emailCredentials, tags); /*FileUtils.cleanDirectory(dir); dir.delete();*/ tempFile.delete(); Unable to delete tempFile from folder till jvm is started.