Try to increase the interval to at least 10 min. There are email providers who limit the frequency an email client is allowed to check for new mail.

I had the frequency set to 10 minutes and this was a problem at that point also. I decrease the frequency thinking it might help.

I just increased the frequency back to 10 minutes. Thanks for the advice, but I don't think that's the root problem in this case.

If 10 min still doesn't work check with your email provider what's allowed.

My problem is not time-based.

If I close Thunderbird and re-open it, hours of emails will appear since the last time Thunderbird was opened. When I click the "go offline" button in Thunderbird and then click it again and click "Get Mail", all of my email is also fetched.

In any other case (regular 10 minute fetches or manually clicking "Get Mail"), my email is not fetched.

Do you get any error message? Can you post your Troubleshooting Information? Help (Alt-H) - Troubleshooting Information

I have not received any error messages.

Here is the troubleshooting information:

 Application Basics

   Name: Thunderbird
   Version: 24.6.0
   User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.6.0
   Profile Directory: Open Directory

             (Unknown location)
   Application Build ID: 20140609100408
   Enabled Plugins: about:plugins
   Build Configuration: about:buildconfig
   Crash Reports: about:crashes
   Memory Use: about:memory

 Mail and News Accounts
   account1:
     INCOMING: account1, , (im) prpl-twitter, plain, 0

   account2:
     INCOMING: account2, , (imap) imap.googlemail.com:993, SSL, passwordCleartext
     OUTGOING: smtp.googlemail.com:465, SSL, passwordCleartext, true
     OUTGOING: smtp.googlemail.com:465, SSL, passwordCleartext, false

   account3:
     INCOMING: account3, , (none) Local Folders, plain, passwordCleartext

   account5:
     INCOMING: account5, , (imap) imap.zoho.com:993, SSL, passwordCleartext
     OUTGOING: smtp.zoho.com:587, alwaysSTARTTLS, passwordCleartext, true

 Extensions
   Enigmail, 1.6, true, {847b3a00-7ab1-11d4-8f02-006008948af5}
   gContactSync, 0.3.6, true, gContactSync@pirules.net
   Lightning, 2.6.5, true, {e2fda1a4-762b-4020-b5ad-a41df1933103}
   Messaging Menu and Unity Launcher integration, 1.3.1, true, messagingmenu@mozilla.com
   Minimize On Start and Close, 1.3.2, true, {480adee0-f020-4fef-917d-b05502b17aaf}
   Provider for Google Calendar, 0.25, true, {a62ef8ec-5fdc-40c2-873c-223b8a6925cc}
   BlunderDelay, 0.5.3, false, blunderdelay@bananabread.net
   Deselect on Delete, 1.1, false, deselectondelete@squib.org
   Follow Reply, 1.0.6, false, FollowReply@luc.pastisman
   Reply Monitor, 0.6, false, replymanager@lin.han
   Send Later, 4.2.4, false, sendlater3@kamens.us
   ThreadVis, 2.2.0, false, {A23E4120-431F-4753-AE53-5D028C42CFDC}
   Thunderbird Conversations, 2.7, false, gconversation@xulforum.org

 Important Modified Preferences

   Name: Value

     accessibility.typeaheadfind.flashBar: 0
     browser.cache.disk.capacity: 358400
     browser.cache.disk.smart_size_cached_value: 358400
     browser.cache.disk.smart_size.first_run: false
     browser.cache.disk.smart_size.use_old_max: false
     extensions.lastAppVersion: 24.6.0
     mailnews.database.global.datastore.id: 30063b95-e57a-48e1-b790-d944afac9a8
     mailnews.database.global.indexer.enabled: false
     mail.openMessageBehavior.version: 1
     network.cookie.prefsMigrated: true
     places.database.lastMaintenance: 1403434143
     places.history.expiration.transient_current_max_pages: 104858
     plugin.importedState: true
     plugin.state.flash: 0
     plugin.state.java: 0
     plugin.state.libnpgoogletalk: 0
     plugin.state.libnplastpass: 0
     plugin.state.libnpo1d: 0
     plugin.state.librhythmbox-itms-detection-plugin: 0
     plugin.state.libtotem-cone-plugin: 0
     plugin.state.libtotem-gmp-plugin: 0
     plugin.state.libtotem-mully-plugin: 0
     plugin.state.libtotem-narrowspace-plugin: 0

 Graphics

     Adapter Description: Intel Open Source Technology Center -- Mesa DRI Intel(R) Haswell Mobile
     Vendor ID: Intel Open Source Technology Center
     Device ID: Mesa DRI Intel(R) Haswell Mobile
     Driver Version: 3.0 Mesa 10.1.3
     WebGL Renderer: false
     GPU Accelerated Windows: 0

     AzureCanvasBackend: cairo
     AzureFallbackCanvasBackend: none
     AzureContentBackend: none

 JavaScript

 Incremental GC: 1

 Accessibility

   Activated: 0
   Prevent Accessibility: 0

 Library Versions

     Expected minimum version
     Version in use

     NSPR
     4.10.2
     4.10.2

     NSS
     3.15.4 Basic ECC
     3.15.4 Basic ECC

     NSS Util
     3.15.4
     3.15.4

     NSS SSL
     3.15.4 Basic ECC
     3.15.4 Basic ECC

     NSS S/MIME
     3.15.4 Basic ECC
     3.15.4 Basic ECC

Edit > Account Settings >Server Settings for the zoho account Advanced >Imap Is this selected? .. "use the idle command if the server supports it"

Yes "use the idle command if the server supports it" is selected.

FYI I tried deleting and recreating the account. I still witness the same problem.

It looks like I also cannot Archive or Delete email either.

What is your anti-virus software?

I do not use any anti-virus software. I am running Ubuntu 14.04.

I can now Archive and Delete emails (I assume this was a temporary Internet issue) but I still have the original problem.

I do not use any anti-virus software. I am running Ubuntu 14.04.

Silly me. Are you running the Ubuntu provided version of Thunderbird from their repository or the vanilla Thunderbird from mozilla.com?

I am using the Ubuntu-provided version.

I'm currently trying to log what's going on using this tutorial <http://www.techienote.com/2010/07/enabling-thunderbirds-logging.html> but I don't know enough about the logs to know whether this is useful yet.

You might try the Mozilla original version if that makes any difference.

The log seem to be showing that the mail is transmitted to Thunderbird but isn't being displayed.

I sent an email with the subject "test11". I think:

1. Sent the email 2. Cleared the log 3. Clicked "Get Mail" for my Zoho account 4. Searched the new log for "test11" and found three lines that look like this (non-consecutive lines):

-50350336[7fdb0e564d00]: 61cd000:imap.zoho.com:S-Sent:CreateNewLineFromSocket: Subject: test11 -50350336[7fdb0e564d00]: ReadNextLine [stream=e55f510 nb=46 needmore=0] -50350336[7fdb0e564d00]: 61cd000:imap.zoho.com:S-Sent:CreateNewLineFromSocket: Content-Type: text/plain; charset=ISO-8859-1

I just tried downloading Thunderbird 24.6.0 for Linux i686 from mozilla.org. When running this version of thunderbird from the command line I only receive the following error:

XPCOMGlueLoad error for file /home/trey/Downloads/thunderbird/libxul.so: libdbus-glib-1.so.2: cannot open shared object file: No such file or directory Couldn't load XPCOM.

Is there an installable .deb file for the Mozilla version of Thunderbird?

After some searching I finally found the 64-bit version of Thunderbird at <ftp://ftp.mozilla.org/pub/thunderbird/releases/latest/linux-x86_64/en-US/>.

I tried the 64-bit version standalone and I experience the same problem.

I just moved my ~/.thunderbird directory to a new location and started Thunderbird with the default settings and no profile. I setup my account again, using the settings recommended by Zoho <https://www.zoho.com/mail/help/thunderbird-imap-access.html>.

I then sent an email to myself with the subject "test15". I hit "Get Mail" a couple times within a few minutes and did not receive an email.

I then: 1. clicked the "go offline" icon in the bottom left corner 2. clicked "Later" at the prompt asking to download emails for offline use 3. clicked the icon again to go back online 4. clicked "Get Mail" and the email I sent to myself was then received

The problem persisted even after completely wiping my Thunderbird settings.

I just setup my account in Evolution and it appears to work.

It seems like Thunderbird only fails at receiving new email when there is an existing IMAP connection to the server. Is there any way to make Thunderbird restart the IMAP connection every time I try to get new mail?