How to Resolve Could Not Parse Mailbox Data Error

Rollins Duke   
Published: May 10th, 2024 • 5 Min Read

When importing emails into Horde webmail via its built-in import feature, there are occasions when it results in a “Could not parse mailbox data” error.

Could not parse mailbox data

It often happens when the user selects the incorrect file or when the mailbox file is corrupt. A large MBOX file that the Horde import function cannot parse is another probable cause.

Anyhow, in this blog, you will learn how to resolve this error, and successfully import mailbox data into the Horde webmail client.

When does the Could Not Parse Mailbox Data Error Occur?

Horde webmail is a part of free web-based groupware. It is integrated into multiple server management software like cPanel & WHM and Plesk.

Horde mail provides a native option to import and export its data. The “could not parse mailbox data” error occurs when importing data fails. The complete process is as follows:

  • Log in to the Horde Webmail client.
  • Right-click on the folder in which you want to import the mailbox data. You can also create a new folder for this task.


  • Select Import from the list of available options.

select import

  • In the window that appears, browse the MBOX file to import into Horde and click OK.

browse the mailbox

  • In case of success, you will get the confirmation message in a green bar. However, when the attempt fails, a red error bar showcasing Could not parse mailbox data will appear.

Could not parse mailbox data

Possible Causes Behind this Horde Import Error

As stated earlier, there are 3 possible reasons that may cause this error:

  1. Wrong file selection
  2. Corrupt mailbox file
  3. MBOX file is too big

We have listed the possible solutions in the next section for all these reasons.

How to Resolve Could Not Parse Mailbox Data Issue

#1 File Selection

The file selected to import into Horde webmail must be an MBOX file. If you have selected ZIP or other files for import, it will result in a “could not parse mailbox data” error.

#2 Corrupt MBOX File

If the mailbox file is corrupt, then Horde will be unable to import the file. In this case, you will need an expert approach i.e., Free MBOX Fixer to repair the corrupt file.

Download for Windows

This free application recovers all the data from a corrupted mailbox and saves them in a healthy MBX file. You can easily import this MBX file in Horde webmail to overcome could not parse mailbox data issue.

The process is as follows:

1. Download and launch the program on your Windows system.

2. Click on the Open button.

click on open button

3. Then, choose the Select file radio button and click on the Browse icon.

click on browse icon

4. After that, navigate to the corrupt MBOX file that you want to import into Horde and click the OK button.

select the corrupt mbox file

5. Let the tool scan and repair the emails in the mailbox file. Once it’s done, select the folder and click the Save button.

click on save button

6. Then, choose the saving path and click the Ok button.

choose the saving path

7. The tool will export all your data into a healthy MBX file. Click OK on the confirmation window.

confirm successful recovery

At last, import this healthy MBX file into Horde mail to receive the green successful confirmation instead of the parsing error.

import file in horde

#3 Too Big Mailbox File

If the mailbox file is too large, it may also result in a “could not parse mailbox data” problem. Hence, it is recommended to split the file into smaller files using the BitRecover MBOX Splitter tool. Once you have the small size MBOX files, you can easily import them into Horde Webmail.

Download software  buy now

Note: If it’s still showing the error, then use the Free MBOX Fixer (mentioned earlier) to repair the file and then import them into Horde. By first splitting the file and repairing them, you can easily circumvent the parsing error and successfully import your mailbox data into the Horde client.

If still Horde import fails… What to do ?

If all of the above steps fails to import MBOX file into your Horde email account then we suggest you to use our MBOX to IMAP import solution. Download it from below link
Download software

When MBOX files are big in size, Horde will be unable to import and handle these large MBOX files. As a result, you may now import MBOX files directly using the IMAP Saving import option. It always works, as we have tried it in our lab for all of our clients who were unable to import MBOX into their Horde email account owing to Horde’s technological constraints.

Observational Verdict

It is evident that sometimes the simple task of importing emails into Horde mail becomes cumbersome with the unexpected could not parse mailbox data error. Fortunately, there are ways to resolve this problem. We have covered the reasons and dedicated solutions to fix this error and help you easily import mailbox data into Horde mail. If you have any further queries, please do not hesitate to contact our support team. We are available 24×7 to resolve such issues.