I am preparing to archive an IMAP mailbox that contains a deeply nested folder structure. The account has separate folders for departments, customers, projects, and yearly correspondence, with several levels of subfolders. I need the exported archive to retain this organization because searching through thousands of messages in a flattened folder would make future retrieval difficult.

I understand that IMAP servers can represent folder names and hierarchy differently. Some providers use separators such as / or ., and folder names may contain spaces or special characters. I am concerned that these differences could affect how folders are interpreted during an export.

Before starting the backup, I want to clarify a few technical details:

• How does an IMAP export process identify parent folders and nested subfolders?

• Can folder separators differ between IMAP providers?

• What happens when two folders have similar names under different parent folders?

• How should special characters and non-English folder names be handled?

• Can I select specific folders while retaining their original hierarchy?

• What is the best way to compare source and destination folder structures after export?

I came across the SysInfoIMAP Backup Tool, which provides folder selection and supports several output formats, including PST, MBOX, EML, and MSG. I am planning to test the export with a mailbox that has multiple nested folders before processing the complete account.

I would also like to verify folder-level message counts and check whether attachments remain accessible after export. This should help identify missing folders or incomplete transfers before the archive is used for long-term storage.

For people who have worked with complex IMAP folder structures, which export format has been the most reliable for preserving folder organization? Are there any provider-specific hierarchy issues that should be checked before beginning a large mailbox backup?