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Summary: Mozilla Thunderbird, an open-source email client, offers robust features but can face issues when its Inbox is full. Solutions include compacting, deleting emails, and adjusting settings.

Mozilla Thunderbird, born as a spin-off from the Mozilla Firefox project, stands as an open-source application. This versatile cross-platform email client boasts a rich set of features, including robust message management, efficient junk filtering, support for extensions and themes, seamless big file handling, and more. Thunderbird empowers users to tailor their email experience while prioritizing security. Moreover, it offers a convenient quick filter feature, enabling users to swiftly sort through their emails. With suitable add-ons, one can also export Thunderbird emails. Despite the innovative elements it offers, users encounter difficulties with reading, sending, and receiving emails when the Thunderbird Inbox reaches its storage limit.

Reasons behind the issue

When the Thunderbird Inbox reaches its capacity, the user encounters an error message. Several factors could contribute to this situation, and we have outlined all potential causes below:

  • The Inbox of the recipient is overflowing with emails, and the server is currently unable to accept any more of them.
  • Over the years, users have accumulated multiple Thunderbird accounts that remain unorganized and cluttered.
  • The Thunderbird mailbox has a maximum storage capacity of 4 gigabytes.
  • The issues with Thunderbird and Windows operating system.
  • An antivirus program or firewall has either removed or quarantined storage files.
Methods to resolve Thunderbird Inbox full cannot receive email

To address this issue, there are two available methods outlined below:

  • Compacting
    When a user deletes emails in Thunderbird, the action doesn’t result in permanent removal from Mozilla Thunderbird. Instead, the emails are merely flagged as deleted or removed from the mail file. To ensure permanent deletion, users must engage in folder compression, a crucial task to prevent potential issues caused by the accumulation of emails. Neglecting this activity, either on a daily or weekly basis, can lead to complications due to the continuous influx of emails. While it is advisable to perform this task daily across all email programs, for added convenience, it can also be carried out on a weekly basis.
  • Deleting emails
    Many individuals opt to reinstall the Thunderbird application in hopes of rectifying the error; however, this action does not resolve the underlying issue, which is email-related. Instead of reinstalling Thunderbird, you have an alternative method at your disposal to address the problem: deleting unwanted and suspicious emails. To achieve this, you can conveniently transfer these emails to a different folder within your local hierarchy. This task can be accomplished efficiently by selecting multiple emails simultaneously using the shift key and then dragging them into a newly created folder.

In the majority of instances, you’ll observe the outcomes once you’ve either relocated or removed emails.
Instead of opting to delete the file, there’s an alternative choice available: you can simply rename the file. This action can help restore the flow of your email once more.
Note: Within Explorer, you’ll notice that each file is accompanied by a corresponding file with the MSF extension. These MSF files should be removed after renaming or deleting the associated file. Failure to do so will result in Thunderbird generating a new index to prevent indexing complications.

Change Deleted Items Settings

To modify the settings for Deleted Items, please follow these steps:

  • Select Menu -> Account Settings.Click on Menu Account settings
  • Afterward, proceed to select “Server Settings” by clicking on on Server Settings
  • Go to the “Leave messages on the server” setting and customize the Thunderbird mailbox storage duration by specifying the number of days that align with your preferences. Then, opt for the “Until I manually delete them” choice.
  • Finally, select the OK option to confirm and save the modifications.
  • Ultimately, your email will be retained on the server until the designated date.

Contact the Email Service Provider

The email service provider has the ability to expand your mailbox capacity. To do so, you can reach out to them and request the removal of certain emails from the server.

Wrapping Up

TThe blog comprehensively outlines various approaches for resolving the Thunderbird error ‘Cannot receive emails when the Inbox is full.’ These methods are user-friendly and do not demand any technical expertise. However, during the deletion process, there is a chance that you may unintentionally remove important emails. You need not worry about this as you can regain your emails by using an innovative tool named Kernel for MBOX to PST. You can convert the MBOX file into various formats such as PST, MSG, RTF, HTML, and many more. This tool enables users to archive their emails across various platforms, including Gmail, Google Apps, and Yahoo. Additionally, it offers advanced filtering capabilities for transferring MBOX mailbox items, allowing users to specify criteria like date ranges and item types. Furthermore, it boasts a user-friendly interface that provides several features, such as MBOX file preview, the ability to split files, support for multiple MBOX email clients, and much more.

Kernel for MBOX to PST