Just like any other file format, MBOX also faces a lot of issues, which needs to be addressed timely to protect the data. For instance, when the size of MBOX increases, you need to reduce its size.
There are multiple issues that users may face while working with MBOX files like error in opening a file, platform incompatibility, corruption of files, etc. Though recent versions of Thunderbird do not put any restrictions on the size of MBOX folders (earlier versions had 4GB as the limit), smaller file sizes are always recommended. This is because the maximum permissible file size depends on the OS file system too. Also, large file sizes can cause some abnormal behavior in some email clients.
MBOX, also known as Berkeley format, is used by many email clients to hold emails. And this format is used by many email client applications including AppleMail, WebMail, PocoMail, Gmail, Postbox, Entourage, Eudora, Opera, Netscape, Thunderbird, Spicebird, Evolution, PowerMail, Claws Mail, SeaMonkey, Sylpheed, GyazMail, Gnu, Mulberry, Sparrow, The Bat!, etc.
Dealing with oversized MBOX files can be a difficult task. However, there are two solutions to which you can look forward to reduce the size of MBOX files:
If you’re not satisfied with the above methods or looking for an automated solution, then it is ideal to convert MBOX file into PST format and then split it into multiple sizes. Kernel MBOX to PST converter can be the handy utility that will allow you to convert all your MBOX files into PST format, and save that file into multiple files based on your requirements.
After converting and splitting the MBOX file to PST format, you can easily open the PST file with any version of MS Outlook to access its data. This is the best solution that works for reducing MBOX file size.
MBOX users can choose different ways reduce the size of their MBOX files. As the first method, they can delete the unwanted emails and then compact the folders. Alternately, they can split MBOX file manually using a text editor. And if none of the above methods works for you, then it would be a great option to convert MBOX file to PST file format with KernelApps tool.