Recently, while helping a colleague switch email clients, I learned how tricky it can be to move between Thunderbird and Outlook. Thunderbird stores everything in MBOX format, while Outlook only accepts PST files. Because of that mismatch, there is no native button or direct import path to export Thunderbird to PST. Manual attempts like IMAP syncing look okay on paper but take a lot of time, configurations, and repeated steps—especially when mailboxes are large or contain attachments. A much simpler method is to use the SysInfo Thunderbird Backup Tool. What stood out to me is its ability to automatically detect Thunderbird profiles without needing manual browsing for file paths. It also supports exporting selective folders using filters, which is helpful when you don’t want to transfer junk or outdated emails. Along with PST, it supports multiple file types and backup options, enabling users to keep local copies for security or record-keeping. For anyone who needs a direct and clean migration workflow, this utility is definitely an efficient approach.