To manually convert PST to Office 365, you can use three methods. First, the Network Upload Method allows you to upload PST files to Office 365 using Azure AzCopy. Second, the Drive Shipping Method involves copying the PST file to a hard drive and shipping it to Microsoft for migration. Third, the Outlook Import Method enables you to import PST files manually through Outlook’s "Import/Export" feature. However, the major drawback of manual migration is that it is complex, time-consuming, and requires technical expertise. Alternatively, the DRS PST to Office 365 Converter is an automated tool that simplifies the process by quickly migrating PST files to Office 365 without data loss.