Batch Thunderbird Email Converter

Simple 3-step process:

1. Download and launch the Thunderbird Email Converter
2. The tool auto-detects ALL your Thunderbird profiles, Official, Microsoft Store and Local Folders
3. Select profiles/folders to convert, choose PST as output format and click Convert

All emails, attachments, folder structure, read/unread status and metadata are preserved in the resulting PST file.

Yes, fully supported. The Thunderbird Email Converter works with both:

• Official Mozilla Thunderbird, downloaded from thunderbird.net (stored in AppData\Roaming)
• Microsoft Store Thunderbird, installed via Windows Store (stored in AppData\Local\Packages)

The tool automatically detects the correct profile location for each installation type and loads all mailboxes on its own. Most other converters only support the Official version.

Yes. The converter detects and displays ALL Thunderbird profiles on your system:

• Default profile, Work profile, Personal profile, all detected automatically
• Select specific profiles or convert all profiles simultaneously
• Each profile's folder structure is maintained in the converted output
• Supports both Official and Microsoft Store profiles together

This is especially useful for users who maintain separate profiles for work and personal emails.

Yes, 100%. Thunderbird Local Folders are fully supported and included by default:

• All emails stored in Local Folders are detected and converted
• Complete subfolder tree is preserved (Projects, Archive, etc.)
• Local Folders are shown separately from account folders for easy identification
• Many other converters skip Local Folders entirely, Univik includes them automatically

Local Folders often contain the most important archived emails that users have manually organized over years.

Yes. The Thunderbird Email Converter preserves the read/unread status of every email:

• Read emails remain marked as read in the converted output
• Unread emails remain marked as unread
• This is critical for forensic investigations and compliance archiving
• Most competing tools do NOT preserve this status

After conversion, you can tell which emails were read and which were unread, exactly as they were in Thunderbird.

Yes, 100%. Every attachment is preserved during conversion:

• Documents (PDF, Word, Excel, etc.)
• Images (JPG, PNG, GIF, etc.)
• Archives (ZIP, RAR)
• Any other file type

Attachments remain correctly linked to their parent emails. You can also extract all attachments separately if needed.

Both are the same Thunderbird application, but installed differently:

Our converter supports BOTH versions and can even convert them simultaneously if you have both installed.

Absolutely safe. The converter operates in read-only mode:

• Your original Thunderbird MBOX files are never modified
• The tool creates new converted files at your specified destination
• Source files remain exactly as they were before conversion
• All profiles and Local Folders are untouched

This is a data-safe conversion process with zero risk to your original emails.

The converter supports multiple output formats:

• Email formats: PST, EML, MSG, MBOX, EMLX
• Document formats: PDF, HTML, RTF, Text
• Cloud services: Gmail, Office 365, IMAP servers

Choose the format that matches your destination email client or archiving requirements.

The free trial lets you:

• Detect and load all Thunderbird profiles (Official, Microsoft Store, Local Folders)
• Preview all your emails with full content and attachments
• Test all conversion features and output formats
• Convert the first 10 items from each folder

Upgrade to the full version for unlimited conversion of all emails across all profiles and Local Folders.