Univik Synology MailPlus Server Email Converter

Excellent  4.8 TrustRating (118 Verified Reviews)

Convert Synology MailPlus Server Emails to PST, PDF, EML and More

Univik Synology MailPlus Server Converter reads standard MBOX email exports from MailPlus Server and converts them to PST, PDF, EML, MSG and other formats on your local Windows machine. Every account, folder, attachment and metadata field is preserved. No connection to the Synology NAS is required after the initial export.

*Free trial converts the first 25 emails per folder. No registration required.

  • No NAS Required After Export: Export MBOX files from MailPlus Server once, then convert on any Windows machine without any Synology connection.
  • All Accounts in One Run: Batch process multiple user account MBOX files. Each account outputs as a separate PST, PDF or EML set with its original folder structure.
  • All MailPlus Versions: Compatible with MBOX exports from MailPlus Server 1.x through MailPlus Server 4.x on DSM 6 and DSM 7.
  • Backup and Archiving: Convert your Synology MailPlus backup MBOX files to PST, PDF or EML for long-term storage independent of the NAS.

Univik Synology MailPlus Server Email Converter

EMAIL ARCHIVE ★ 2025 ★

Trusted for NAS Email Migration

IT administrators and system managers use Univik to export and archive Synology MailPlus Server accounts when decommissioning NAS hardware or migrating to cloud email.

 MailPlus Server Email Data Extracted

 Key Features

Why Choose Univik MailPlus Converter

Built for IT administrators and system managers migrating away from Synology MailPlus or archiving historical accounts.

No NAS required

No Synology NAS Required After Export

Once MBOX files are exported from MailPlus Server using the DSM interface, Univik Converter works entirely on your local Windows machine. No VPN, no NAS IP, no DSM login. This makes conversion practical when decommissioning a NAS, restoring from backup or working from a different site.

Folder structure preserved

Folder Structure Fully Preserved

MailPlus Server organises emails into Inbox, Sent, Drafts, Trash and custom user-created folders. Univik Converter reads the full MBOX folder hierarchy and recreates it in the output. PST output mirrors the folder structure as Outlook folders. EML output creates matching directories. No emails are ever merged or flattened.

Batch all accounts

Batch Convert All User Accounts

Export MBOX files for every MailPlus user account into a folder, then run Univik Converter once. Each account is processed in sequence and generates its own output file named after the account. For organisations with 50 or 500 accounts, this eliminates the manual effort of converting one account at a time.

Attachments preserved

Attachments and Metadata Preserved

All file attachments are extracted from the MBOX source and embedded in the output. Email metadata including From, To, CC, BCC, Subject, Date, Message-ID and all RFC 5322 headers are preserved exactly as stored. No attachment is lost and no header is stripped during conversion.

Date and folder filters

Date Range and Folder Filters

Convert only emails within a specific date range, from specific folders or matching a subject keyword. Filters let you extract only the legally required emails for a compliance request, or only the last six months of a departing employee's inbox rather than their entire seven-year email history.

100% offline

100% Offline and Confidential

Business email archives contain highly sensitive communications. Univik Converter processes every MBOX file locally on your Windows machine. No emails are transmitted to any server, no cloud processing occurs and no internet connection is required. The conversion log records every file processed for internal audit purposes.

 Export Formats

Export MailPlus Emails to 20+ Formats

Every format available for converting your Synology MailPlus Server email archive. Import into a new mail system, archive for compliance or open in any email client.

Email Client Formats

📦
PST
Outlook Data
✉️
EML
Email Message
📨
MSG
Outlook Message
📫
MBOX
Unix Mailbox
📧
EMLX
Apple Mail
📮
MBX
Mailbox File

Document and Archive Formats

📄
PDF
Portable Document
📝
DOC / DOCX
Word Document
📋
RTF
Rich Text Format
📃
TXT
Plain Text
📊
CSV
Spreadsheet
📑
XPS
XML Paper Spec

Web and Structured Formats

🌐
HTML
Web Page
📑
MHTML
Web Archive
🗂️
JSON
Structured Data
📰
TNEF
Transport Neutral
🔖
ICS
Calendar Events
👤
VCF
Contacts vCard

All 20+ formats available in the full version. View the complete format list on the Univik Email Converter page.

 Data Integrity

Everything Preserved During Conversion

Every element of your MailPlus Server email data is carried through the conversion process without modification.

Read/Unread Status
📎
All Attachments
Flagged / Starred
📁
Folder Structure
👥
From / To / CC / BCC
🖼️
Inline Images
💬
Subject Line
✍️
Email Signatures
📅
Date & Time
🔗
Hyperlinks
📋
Email Headers
🎨
HTML Formatting
🔒
MIME Metadata
🔴
Email Priority
🏷️
Folder Names
🏷️
MailPlus Labels

 Simple Pricing

Choose Your License

One-time payment. Lifetime license. No subscription. Free updates included.

Free Trial

Try Free

$0 forever
Download Free
  • 10 emails per folder
  • All export formats
  • Full preview
  • No time limit
Most Popular
Personal

Personal License

$99 lifetime
One-time payment
Buy Personal

30-day money-back guarantee

  • Unlimited conversion
  • All 20+ export formats
  • 1 PC activation
  • Free lifetime updates
  • Email support
Business

Business License

$299 lifetime
Buy Business
  • Everything in Personal
  • 5 PC activations
  • Commercial use
  • Priority phone support
  • Volume discounts

 How It Works

MailPlus to PST in 3 Steps

Export from the NAS, convert on Windows, import into your destination system.

1

Export MBOX from MailPlus Server

In Synology DSM, go to MailPlus Server and use the mail export function to save user account mailboxes as MBOX files. Copy the exported files to a Windows PC via SMB share, USB or any file transfer method. Keep the folder structure intact for accurate account identification.

Alternatively, use the MailPlus web client PST export for individual accounts.

2

Load and Configure

Open Univik MailPlus Converter. Browse to a single MBOX file or a folder containing multiple account exports for batch processing. Preview shows email counts, folder structure and date ranges for each account. Apply any date or folder filters needed before conversion.

3

Convert and Import

Select output format and destination folder. Click Convert. Each account generates its own output file. Import PST files directly into Outlook or Microsoft 365 . Converting Synology MailPlus to Outlook is simpler this way takes one PST import after conversion. Move EML files into Thunderbird or any IMAP server. Send PDF archives to your compliance storage.

 Use Cases

Who Converts MailPlus Server Emails

The organisations and IT teams that rely on Univik MailPlus Converter.

NAS decommission

NAS Decommission and Replacement

When a Synology NAS reaches end of life or is replaced, IT teams need to preserve all MailPlus email accounts before powering down the hardware. Univik Converter processes the exported MBOX archive into PST or EML so all historical email remains accessible after the NAS is gone.

Cloud migration

Migration to Cloud Email

Organisations moving from Synology MailPlus to Microsoft 365, Google Workspace or another cloud mail platform need their historical emails in PST or EML format for upload. Univik Converter produces import-ready output for all major cloud migration tools without any intermediate reformatting step.

Compliance archiving

Compliance and Legal Archiving

Regulated industries must retain business email for three to seven years. Converting MailPlus accounts to PDF or EML creates a compliant, readable archive independent of the NAS infrastructure. Each PDF email record includes all headers and metadata required for audit trail and legal disclosure purposes.

Employee off-boarding

Employee Off-Boarding

When employees leave, IT managers need to archive their MailPlus mailbox before the account is deactivated. Univik Converter exports the departing employee's full account including sent items, drafts and any custom folders to PST or EML for handover to their manager or storage in the compliance archive.

Disaster recovery

Disaster Recovery and Backup Validation

Organisations running MailPlus Server use Univik Converter to validate MBOX backup archives by converting them and verifying email integrity. Converting to EML or PST and spot-checking emails confirms that the backup is readable and complete before a real disaster makes this question urgent.

 MailPlus Server Reference

About Synology MailPlus Server

What MailPlus Server is, how it stores email and what the conversion process involves technically.

What is Synology MailPlus Server?

Synology MailPlus Server is an on-premise email server package for Synology NAS devices running DSM 6.0 or later. It provides SMTP, POP3 and IMAP services, letting small and medium businesses run a fully managed email server on Synology hardware.

MailPlus Server stores all emails in standard MBOX format on the NAS filesystem. Since MBOX is an open standard, the data can be read by any MBOX-compatible tool once exported from the NAS. MailPlus MBOX to PST conversion is the most common operation after a Synology NAS email export.

Quick Reference

DeveloperSynology Inc. (Taiwan)
PlatformDSM 6.0 / 7.x
Email storageMBOX (standard Unix format)
ProtocolsSMTP, POP3, IMAP
Built-in exportPST only (web client, NAS required)
Current versionMailPlus 4.x (4.0 Beta 2026)
LicenseFree for 5 accounts, paid beyond
Official docsSynology Knowledge Center

Why the Built-in Export Falls Short

  • Requires NAS online
    PST export only works while the NAS is running and accessible.
  • One account at a time
    No batch export. Each account needs a separate export action.
  • PST format only
    No PDF, EML, MSG, HTML or MBOX output options natively.
  • Univik Converter
    Batch convert all accounts to 20+ formats. NAS not required.

Synology MailPlus Version History

From Mail Server to MailPlus 4.0

Synology started with a basic Mail Server package in DSM, then replaced it with the feature-rich MailPlus Server, adding high-availability clustering, the MailPlus web client, Bitdefender antivirus integration and admin-level export and audit tools.

MailPlus Server 1.x MailPlus Server 2.x MailPlus Server 3.x MailPlus Server 4.x DSM 6 / DSM 7 MBOX storage

Version Timeline

Pre-2016
Synology Mail Server: basic SMTP/IMAP package
2016
MailPlus Server 1.0: high-availability and web client added
2019
MailPlus Server 2.0: antivirus and audit logging
2022
MailPlus Server 3.x: PST export and mail recall
2026
MailPlus Server 4.0 Beta: domain sharing, new features
Univik Synology MailPlus Converter Features

 Why Univik

Email Conversion Built for IT Teams

Univik has been building email archive converters since 2013. The MailPlus converter is part of a comprehensive email archive toolkit that covers Mail Assure, Mimecast, Google Vault and 20+ other email archive formats.

  • Reads standard MBOX format exported from all MailPlus Server versions.
  • Batch convert all user accounts from a single folder in one operation.
  • Full folder hierarchy preserved in every output format.
  • All attachments and RFC 5322 headers included in output.
  • Date range, folder and keyword filters for targeted extraction.
  • Conversion log with per-email status for audit documentation.
  • 100% offline. No emails transmitted. No cloud dependency.
  • Free trial. No registration. 30-day money-back guarantee.

 Customer Reviews

Trusted by IT Teams Worldwide

Rated 4.8 out of 5 by verified users including system administrators and IT managers who converted MailPlus Server accounts.

★★★★★ 4.8 / 5  (118 reviews)
★★★★★

"We decommissioned our Synology DS920+ and needed to export 12 user accounts from MailPlus. Converted all accounts to PST in under an hour. The folder structure was exactly preserved in Outlook."

Mark H.
IT Manager  ·  Leeds, UK
★★★★★

"Needed to archive 5 years of MailPlus emails to PDF for a compliance audit. Batch converted 3 accounts with date filters. Each PDF has the full headers. Exactly what our auditor needed."

Priya N.
Compliance Officer  ·  Singapore
★★★★★

"Migrating our office from MailPlus to Microsoft 365. Converted 28 MBOX exports to PST over a weekend. Imported directly into Exchange Online without any reformatting. Saved us two days."

Tobias W.
Systems Administrator  ·  Hamburg, Germany

 FAQs

Common MailPlus Converter Questions

Answers to what IT administrators ask most about converting Synology MailPlus Server email accounts.

No. Once you have exported the MBOX files from MailPlus Server using the DSM interface, Univik Converter reads those files locally on your Windows PC without any connection to the Synology NAS. This is particularly useful when the NAS is being decommissioned, when you are restoring from a backup on a different machine, or when you need to process historical archives from a NAS that is no longer accessible.

Synology MailPlus Server stores all emails in standard MBOX format on the NAS filesystem. MBOX is an open Unix mail storage standard used by many mail servers and clients including Mozilla Thunderbird and Apple Mail. Each user account has its own MBOX mailbox structure. Because MBOX is an open format, the data can be read by any MBOX-compatible tool after export from the NAS.

Yes. Export the MBOX files for all user accounts into a single folder, then point Univik Converter at that folder. The converter identifies each account from its MBOX file, processes them sequentially and generates a separate output file per account named after the source account. There is no account limit in the paid version, making this practical for organisations with dozens or hundreds of accounts.

Yes to both. All file attachments are extracted and embedded in the output exactly as in the original MBOX. In PST output, attachments appear within each Outlook message. In EML output, attachments are saved as separate files alongside the .eml file. The folder hierarchy from MailPlus Server including Inbox, Sent, Drafts, Trash and any custom folders is fully preserved and recreated in the output.

All MailPlus Server versions are supported: MailPlus Server 1.x through the current 4.x release, on both DSM 6.0 and DSM 7.x. The converter reads standard MBOX format which MailPlus Server has used consistently across all versions, so any version that produces a standard MBOX export is compatible.

Yes. PDF output is the most suitable format for compliance archiving and legal discovery. Each email exports as a self-contained PDF with all headers (From, To, CC, BCC, Subject, Date, Message-ID) and the full message body visible. The converter generates a log file recording each source file, its email count and the output path, which can be retained as part of your audit trail.

Completely. Univik MailPlus Converter processes all MBOX files locally on your Windows machine. No email content is transmitted to any server or cloud service. No internet connection is required during conversion. Your organisation's business communications, which may contain confidential client or financial information, never leave your local machine throughout the entire process.

PST is the most direct format for importing into Microsoft 365 or Exchange. The PST output from Univik Converter is fully compatible with the Outlook Import and Export Wizard and with the Exchange Admin Center's PST import service. Each converted PST file contains all folders and emails from the source account and imports in a single operation without any intermediate reformatting.

Univik MailPlus Converter runs on Windows 7, 8, 8.1, 10 and 11 (both 32-bit and 64-bit). Minimum 4 GB RAM is recommended for large MBOX archives. You need approximately 100 MB of disk space for the installation plus output file space. No internet connection is required during conversion. The free trial converts the first 25 emails per folder so you can verify output quality before purchasing.

Convert Your MailPlus Server Email Archive

Free trial. No NAS required. No registration. Your emails stay on your machine.

Windows 7, 8, 10, 11  |  100% offline  |  30-day money-back guarantee

Written by Univik Research Team

The Univik Research Team has been building email archive conversion software since 2013. Our engineers work with MBOX, PST, EML, MSG and all major email archive formats. This page covers Synology MailPlus Server email export and conversion, tested against real MailPlus MBOX exports from DSM 6 and DSM 7 environments. For professional email migration assistance, see our email migration service.

Related converters: Mail Assure  |  Mimecast  |  Google Vault  |  MailStore Server