Roundcube webmail not receiving emails can be fixed by freeing up the server storage, verifying email port configurations, fixing DNS routing and MX records, reviewing Spam Filters and Security Protocols, or resolving browser and Caching Issues.

Discovering Roundcube emails not showing up in the inbox can really get on your nerves and disrupt your entire workflow. Especially when you’re finding critical business messages or waiting for an urgent password reset link.

A webmail server cannot receive incoming mail often due to an exhausted storage quota, incorrect server configurations, DNS routing, or client-side caching. So, if your incoming emails stopped in Roundcube, use the proven methods in this detailed troubleshooting guide.

So, let’s check out how to fix Roundcube webmail not receiving emails!

What You’ll Learn Hide
  1. #1: Free up the Server Storage Limit
  2. #2: Secure Your Data (Before Advanced Troubleshooting)
  3. #3: Verify Email Client Port Configurations
  4. #4: Fix DNS Routing and MX Records
  5. #5: Audit Spam Filters and Security Protocols
  6. #6: Resolve Browser and Caching Issues
  7. The Takeaway
  8. FAQs (Frequently Asked Questions)

#1: Free up the Server Storage Limit

Maxed-out disk space is one of the key reasons why you’re experiencing Roundcube webmail not receiving emails. When you hit the allocated disk space, the server will immediately start discarding incoming emails. Hence, to fix the Roundcube not working issue, maintain the server storage limit. To do so, you can delete old, unwanted emails or upgrade the current hosting plan.

So, before we dive into advanced server routing, let’s begin with the most common culprits: a mailbox full error.

How do I check if my email storage quota is full in cPanel?

  • Log into the cPanel dashboard.
  • Go to the cPanel email accounts section.
  • Find the targeted email address >> click on the Manage or check the storage bar.
  • Check the Email storage quota. If it’s full, delete the old emails to upgrade the hosting plan.

Pro-Tip: Make sure to empty the junk mail folder and trash bin, as these folders consume the total storage limit.

#2: Secure Your Data (Before Advanced Troubleshooting)

Data preservation is a primary step that shouldn’t be skipped when dealing with cPanel webmail missing emails or switching web hosts due to a persistent webmail server outage. The reason is quite obvious: altering DNS routing or deleting server configurations can accidentally erase existing mail.

And to ensure a rapid and secure email backup, IT professionals strongly advocate for Roundcube Backup Wizard. A top-rated, corporate-ready backup tool devised to handle any-to-any Roundcube backup without any data loss from 1 to 1000+ users on Windows and Mac.

Here are the incredible and highly effective features of this backup tool that positions itself as the first choice for Individual users and IT administrators:

  • Universal IMAP Server Support: This B2B level tool offers complete IMAP server support for Roundcube, Gmail, Outlook, iCloud, and more.
  • Multiple File Formats: It allows you to download your Roundcube emails into PST, MBOX, EML, MSG, & PDF. Mac users can even download emails in EMLX, TXT, and HTML format.
  • Bulk IMAP Backup: It allows you to perform multi-account backup of the same or specific IMAP host at once.
  • Maintains Folder Hierarchy: This robust backup tool is proficient in preserving the original folder hierarchy during the whole backup process.
  • Data-Filter Option: For backing up emails based on specific date ranges, it provides the date-filter option.
  • Delta Backup Feature: Want to backup only newly arrived emails? Use the delta backup feature that syncs only fresh emails after the backup.
  • Migrates Complete IMAP Server Mailbox Data: It securely migrates entire IMAP server mailbox data (messages, folders, contacts, calendars, metadata, etc) to another without any data loss.
  • Backup Verification: This Roundcube backup wizard also provides a combined CSV report of all backed-up email accounts.

So, bypass the error-prone, time-consuming manual backup method and choose SysTools’ advanced backup tool to securely store complete mailbox data locally.

#3: Verify Email Client Port Configurations

Verifying email client port configurations is another workaround to bypass the Roundcube webmail not receiving emails issue. Using third-party applications (like Outlook or Apple Mail) in conjunction with webmail or misconfigured backend settings often results in the IMAP server not fetching emails in Roundcube.

Therefore, to ensure secure and reliable mail delivery, your ports must be configured correctly with the standard SSL/TLS protocols. Otherwise, it will always end up in a classic “unable to fetch” error.

So, what are the correct IMAP port settings for Roundcube?

  • IMAP ports (143/993): Always use Port 993 for secure SSL/TLS IMAP. Port 143 is non-secure.
    POP3 Settings: Use Port 995 for secure POP3. The right configuration for downloading mail off the server permanently. Choose 110 for non-secure POP3.
  • But how to fix Roundcube webmail sending but not receiving emails?
    If you can send emails successfully but cannot receive them, it means SMTP is working, and the issue is connected to your incoming IMAP/POP3 routing.
  • To fix this, verify the firewall is not blocking ports that are triggering the issue. Restrictive server firewalls (like ConfigServer Security & Firewall (CSF) often block port 25 or 993, disrupting the flow of incoming mail.

Related Reads: Roundcube IMAP Settings for Outlook & Gmail Apps

#4: Fix DNS Routing and MX Records

Incorrect MX records can also be responsible for the Roundcube not working issue. Because when an email is sent to you, the sender’s server queries your domain’s DNS to determine the delivery destination. And when the MX records are incorrect, the email gets lost.

Hence, fixing DNS routing and MX records becomes a non-negotiable step to settle down
Roundcube not getting new emails.

So, how do I point my MX records to my webmail domain correctly?

  • Log in to the hosting account >> Access the cPanel DNS settings.
  • Open the Zone editor >> locate the domain >> click Manage.
  • Filter the MX records.

Note: Ensure your MX records point to your correct mail server with a priority of 0 (or your host’s specified priority).

  • Lastly, confirm the mail routing is configured to “Local Mail Exchange” (if your emails are hosted on the same cPanel server. Because the remote routing will prompt the server to reject local deliveries.

#5: Audit Spam Filters and Security Protocols

Review spam filters and security protocols, as emails may land perfectly but are hidden from the primary inbox view due to active spam filters (like Apache SpamAssassin). It can mimic the effects of the Roundcube webmail not receiving emails error.

Quick Explanation: Apache SpamAssassin is a robust spam filter integrated into most cPanel environments.

So, is SpamAssassin blocking my incoming emails in Roundcube?

  • Yes, Apache SpamAssassin can block incoming emails in Roundcube entirely if its threshold is set too aggressively (like a score of 2 or 3). It will flag legitimate emails and hide them from the primary inbox view.
  • To fix this, configure the spam score sensitivity to 5 (ideal range). Additionally, make sure to check the custom email filters and global forwarding rules. This confirms that messages aren’t being automatically purged or shifted to a blackhole folder.

#6: Resolve Browser and Caching Issues

To fix Roundcube webmail not receiving emails, you must confirm that the server is actually failing or your browser is refusing to display the latest data. And this brings us to one of the most asked queries when dealing with “Incoming emails stopped in Roundcube” or “Roundcube inbox not updating”:

Does clearing my browser cache fix Roundcube not updating?

Absolutely Yes! As we all know, all browsers store static files to load pages faster. And when these respective files get corrupted, it triggers Roundcube inbox not updating -even though the server has securely received the mail.

  • Browser Cache and Cookies: Wipe out the cache and cookies in the browser’s privacy settings. It will force Roundcube to load the updated data from the server.
  • Outdated Browser Version: Older browser versions can break modern webmail JavaScript scripts. So, ensure that your Chrome, Firefox, or Safari is up to date.
  • Security Settings: Make sure any strict browser extensions (such as ad-blockers) or local security settings are not interfering with the background sync scripts.

Also Check Out: How to Export Roundcube Emails to Gmail? Best 6 Ways

The Takeaway

This comprehensive guide shares the 6 basic-to-advanced troubleshooting methods to fix Roundcube webmail not receiving emails. Each fix has the potential to settle down the issue of incoming emails stopped in Roundcube. So, check them out one by one and continue the flow of your Roundcube emails.

And if you find yourself stuck in the middle of any process or encounter other technical issues, contact us at [email protected] and [email protected].

People Also Find Helpful:

FAQs (Frequently Asked Questions)

Q.1: Why are my emails not showing up in my Roundcube inbox?
Roundcube webmail not receiving emails happens due to four major reasons:

  • Exhausted Storage Quota
  • DNS Routing pointing to the wrong server destination
  • Firewall is blocking crucial IMAP/POP3 Ports.
  • Aggressive Spam Filters

Q.2: Why am I receiving some emails but not others in Roundcube?
Sometimes, Roundcube blocks certain domains (like Gmail or Outlook) because of DNS propagation or sender authentication. So, if you have recently updated hosts, wait till the DNS changes propagate globally. Alternatively, verify the sender’s domain is not struggling with SPF, DKIM, or DMARC checks.

Q.3: Why can I see emails in Roundcube but not on my iPhone/Android?
It happens due to an IMAP sync issue. Verify that your phone’s IMAP port (993) and confirm that your mobile device isn’t accidentally configured with POP3 settings. It can fetch emails off the server and conceal them from other devices.

Q.4: Do senders get a bounce-back message if my Roundcube inbox is full?
Yes, mostly. The sender will usually receive a “Mail Delivery Subsystem” bounce-back email stating “552 5.2.2 Quota exceeded or Mailbox full. And, if they aren’t receiving bounce-backs, their sent email might be routing to the wrong server completely (review MX records).

Q.5: My storage isn’t full, so why is Roundcube still rejecting emails?
You may have hit your Inode limit. In cPanel, an “inode” represents a single file (one email = one file). Exceeding the web host’s maximum file count limit will prompt the server from accepting new emails. To fix this, archive old emails or back them up locally using a robust, professional email backup downloader.

Q.6: Why are emails delayed by several hours in reaching my Roundcube inbox?
Emails are delayed in reaching the Roundcube inbox due to greylisting (a spam blocker feature on the server that temporarily blocks emails from unknown senders. Email delays (latency) can also occur if the sender’s mail server is blacklisted or experiencing heavy traffic.