Do you have a crash ID? https://support.mozilla.org/kb/mozilla-crash-reporter-tb#w_viewing-crash-reports

Crash ID: bp-c98a6492-6389-4733-a808-c32890170710

Is there any difference when you start Thunderbird in safe mode? https://support.mozilla.org/kb/safe-mode-thunderbird

Okay. It started up fine in Safe Mode. However, I closed the Safe Mode version to see if the regular Thunderbird would start and it didn't.

Among other things, safe mode disables all extensions. Disable all extensions, and enable them one by one until you find the culprit.

I'm not sure exactly how to do that. In Safe Mode, I went to the Add-ons Manager and it said I didn't have "any add-ons of this type installed." For Plug-ins, I had several versions of Shockwave but even when they are all disabled and set to "Never Activate," I can't then get the regular Thunderbird to start up.

Also, when I start the Safe Mode, I tried selecting both "Disable all add-ons" and "Reset toolbars and Controls" and then selecting "Make Changes and Restart" and I continue to get the crash report pop-up.

I can only work things in Safe Mode. Any advice?

Please post your Troubleshooting Information. At the top right of the Thunderbird window, click the menu button , then select Help > Troubleshooting Information. Press the "Copy text to clipboard button" and paste the information into your reply.

Application Basics

   Name: Thunderbird
   Version: 52.2.1
   User Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.2.1
   Profile Folder: Open Folder

             (Local drive)
   Application Build ID: 20170622064432
   Enabled Plugins: about:plugins
   Build Configuration: about:buildconfig
   Memory Use: about:memory
   Profiles: about:profiles

 Mail and News Accounts
   account1:
     INCOMING: account1, , (none) Local Folders, plain, passwordCleartext

   account2:
     INCOMING: account2, , (pop3) mail.comcast.net:995, SSL, passwordCleartext
     OUTGOING: , smtp.comcast.net:465, SSL, passwordCleartext, true

   account3:
     INCOMING: account3, , (pop3) psumail.pdx.edu:110, plain, passwordCleartext
     OUTGOING: , smtp.comcast.net:465, SSL, passwordCleartext, true

 Crash Reports
   https://crash-stats.mozilla.com/report/index/bp-c98a6492-6389-4733-a808-c32890170710 (7/10/2017)
   https://crash-stats.mozilla.com/report/index/bp-61b078f0-5bd6-4540-a1a0-d89100170710 (7/9/2017)
   https://crash-stats.mozilla.com/report/index/bp-6186ae0a-fdb3-46cc-9f25-cb7fb0170710 (7/9/2017)
   https://crash-stats.mozilla.com/report/index/bp-941e8887-c2a9-49f0-95e4-bda390170710 (7/9/2017)
   https://crash-stats.mozilla.com/report/index/bp-1997e230-7873-46e0-8ee1-aca530170710 (7/9/2017)

 Extensions

 Important Modified Preferences

   Name: Value

     accessibility.lastLoadDate: 1499721691
     accessibility.typeaheadfind.flashBar: 0
     browser.cache.disk.capacity: 358400
     browser.cache.disk.filesystem_reported: 1
     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
     browser.display.screen_resolution: 96
     dom.apps.reset-permissions: true
     extensions.lastAppVersion: 52.2.1
     font.internaluseonly.changed: false
     font.name.monospace.el: Consolas
     font.name.monospace.tr: Consolas
     font.name.monospace.x-baltic: Consolas
     font.name.monospace.x-central-euro: Consolas
     font.name.monospace.x-cyrillic: Consolas
     font.name.monospace.x-unicode: Consolas
     font.name.monospace.x-western: Consolas
     font.name.sans-serif.el: Calibri
     font.name.sans-serif.tr: Calibri
     font.name.sans-serif.x-baltic: Calibri
     font.name.sans-serif.x-central-euro: Calibri
     font.name.sans-serif.x-cyrillic: Calibri
     font.name.sans-serif.x-unicode: Calibri
     font.name.sans-serif.x-western: Calibri
     font.name.serif.el: Cambria
     font.name.serif.tr: Cambria
     font.name.serif.x-baltic: Cambria
     font.name.serif.x-central-euro: Cambria
     font.name.serif.x-cyrillic: Cambria
     font.name.serif.x-unicode: Cambria
     font.name.serif.x-western: Cambria
     font.size.fixed.el: 14
     font.size.fixed.tr: 14
     font.size.fixed.x-baltic: 14
     font.size.fixed.x-central-euro: 14
     font.size.fixed.x-cyrillic: 14
     font.size.fixed.x-unicode: 14
     font.size.fixed.x-western: 14
     font.size.variable.el: 17
     font.size.variable.tr: 17
     font.size.variable.x-baltic: 17
     font.size.variable.x-central-euro: 17
     font.size.variable.x-cyrillic: 17
     font.size.variable.x-unicode: 17
     font.size.variable.x-western: 17
     gfx.direct3d.last_used_feature_level_idx: 0
     mail.openMessageBehavior.version: 1
     mail.winsearch.firstRunDone: true
     mailnews.database.global.datastore.id: d9f341ce-0d47-48e3-bf29-85346f0e604
     mailnews.database.global.views.conversation.columns: {"threadCol":{"visible":true,"ordinal":"1"},"flaggedCol":{"visible":true,"ordinal":"23"},"attachmentCol":{"visible":fals…
     mailnews.database.global.views.global.columns: {"threadCol":{"visible":true,"ordinal":"1"},"flaggedCol":{"visible":true,"ordinal":"23"},"attachmentCol":{"visible":fals…
     media.gmp.storage.version.observed: 1
     network.cookie.prefsMigrated: true
     network.predictor.cleaned-up: true
     places.database.lastMaintenance: 1499277015
     places.history.expiration.transient_current_max_pages: 122334
     plugin.importedState: true
     plugin.state.flash: 0
     plugins.update.notifyUser: true
     print.print_printer: HP Photosmart 3200 series
     print.printer_HP_LaserJet_1020.print_bgcolor: false
     print.printer_HP_LaserJet_1020.print_bgimages: false
     print.printer_HP_LaserJet_1020.print_command:
     print.printer_HP_LaserJet_1020.print_downloadfonts: false
     print.printer_HP_LaserJet_1020.print_evenpages: true
     print.printer_HP_LaserJet_1020.print_footercenter:
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     print.printer_HP_LaserJet_1020.print_footerright: &D
     print.printer_HP_LaserJet_1020.print_headercenter:
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     print.printer_HP_LaserJet_1020.print_margin_bottom: 0.5
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     print.printer_HP_LaserJet_1020.print_oddpages: true
     print.printer_HP_LaserJet_1020.print_orientation: 0
     print.printer_HP_LaserJet_1020.print_pagedelay: 500
     print.printer_HP_LaserJet_1020.print_paper_data: 1
     print.printer_HP_LaserJet_1020.print_paper_height: 11.00
     print.printer_HP_LaserJet_1020.print_paper_size: 0
     print.printer_HP_LaserJet_1020.print_paper_size_type: 0
     print.printer_HP_LaserJet_1020.print_paper_size_unit: 0
     print.printer_HP_LaserJet_1020.print_paper_width: 8.50
     print.printer_HP_LaserJet_1020.print_printer: HP LaserJet 1020
     print.printer_HP_LaserJet_1020.print_reversed: false
     print.printer_HP_LaserJet_1020.print_scaling: 1.00
     print.printer_HP_LaserJet_1020.print_shrink_to_fit: true
     print.printer_HP_LaserJet_1020.print_to_file: false
     print.printer_HP_Photosmart_3200_series.print_bgcolor: false
     print.printer_HP_Photosmart_3200_series.print_bgimages: false
     print.printer_HP_Photosmart_3200_series.print_command:
     print.printer_HP_Photosmart_3200_series.print_downloadfonts: false
     print.printer_HP_Photosmart_3200_series.print_evenpages: true
     print.printer_HP_Photosmart_3200_series.print_footercenter:
     print.printer_HP_Photosmart_3200_series.print_footerleft: &PT
     print.printer_HP_Photosmart_3200_series.print_footerright: &D
     print.printer_HP_Photosmart_3200_series.print_headercenter:
     print.printer_HP_Photosmart_3200_series.print_headerleft: &T
     print.printer_HP_Photosmart_3200_series.print_headerright: &U
     print.printer_HP_Photosmart_3200_series.print_in_color: true
     print.printer_HP_Photosmart_3200_series.print_margin_bottom: 0.5
     print.printer_HP_Photosmart_3200_series.print_margin_left: 0.5
     print.printer_HP_Photosmart_3200_series.print_margin_right: 0.5
     print.printer_HP_Photosmart_3200_series.print_margin_top: 0.5
     print.printer_HP_Photosmart_3200_series.print_oddpages: true
     print.printer_HP_Photosmart_3200_series.print_orientation: 0
     print.printer_HP_Photosmart_3200_series.print_pagedelay: 500
     print.printer_HP_Photosmart_3200_series.print_paper_data: 1
     print.printer_HP_Photosmart_3200_series.print_paper_height: 11.00
     print.printer_HP_Photosmart_3200_series.print_paper_size: 0
     print.printer_HP_Photosmart_3200_series.print_paper_size_type: 0
     print.printer_HP_Photosmart_3200_series.print_paper_size_unit: 0
     print.printer_HP_Photosmart_3200_series.print_paper_width: 8.50
     print.printer_HP_Photosmart_3200_series.print_printer: HP Photosmart 3200 series
     print.printer_HP_Photosmart_3200_series.print_reversed: false
     print.printer_HP_Photosmart_3200_series.print_scaling: 1.00
     print.printer_HP_Photosmart_3200_series.print_shrink_to_fit: false
     print.printer_HP_Photosmart_3200_series.print_to_file: false
     security.OCSP.disable_button.managecrl: false
     security.sandbox.content.tempDirSuffix: {5bbed5cd-33d7-4f05-b4c8-4e5e6d2e83e2}

 Graphics

     GPU #1
     Description: Intel(R) HD Graphics Family
     Vendor ID: 0x8086
     Device ID: 0x0a16
     RAM: Unknown
     Drivers: igdumdim64 igd10iumd64 igd10iumd64 igdumdim32 igd10iumd32 igd10iumd32
     Driver Version: 10.18.10.3308
     Driver Date: 9-16-2013

     GPU #2
     Description: NVIDIA GeForce GT 745M
     Vendor ID: 0x10de
     Device ID: 0x0fe3
     RAM: 2048
     Drivers: nvd3dumx,nvwgf2umx,nvwgf2umx nvd3dum,nvwgf2um,nvwgf2um
     Driver Version: 9.18.13.3165
     Driver Date: 10-23-2013

     Features
     Direct2D: false
     DirectWrite: true (6.3.9600.17111)
     WebGL Renderer: false

     AzureCanvasBackend: skia
     AzureCanvasAccelerated: 0
     AzureFallbackCanvasBackend: cairo
     AzureContentBackend: skia

 JavaScript

 Incremental GC: 1

 Accessibility

   Activated: 0
   Prevent Accessibility: 0

 Library Versions

     Expected minimum version
     Version in use

     NSPR
     4.13.1
     4.13.1

     NSS
     3.28.5
     3.28.5

     NSS Util
     3.28.5
     3.28.5

     NSS SSL
     3.28.5
     3.28.5

     NSS S/MIME
     3.28.5
     3.28.5

Please try the following. Locate your Thunderbird profile folder. https://support.mozilla.org/en-US/kb/profiles-where-thunderbird-stores-user-data#w_how-to-find-your-profile

Close Thunderbird.

Use Windows Explorer for the following. Within the profile folder there's an 'extensions' sub-folder. Underneath 'extensions' locate the folder 'e2fda1a4-762b-4020-b5ad-a41df1933103'.

Delete the folder 'e2fda1a4-762b-4020-b5ad-a41df1933103'.

Start Thunderbird.

I deleted that folder in the extensions sub-folder and then tried to start Thunderbird regularly. It wouldn't restart regularly but still can in Safe Mode.

The folder 'e2fda1a4-762b-4020-b5ad-a41df1933103' belongs to Lightning, the Thunderbird calendar extension. Lightning didn't show up in your Troubleshooting Information underneath 'Extensions', hence the suggestion to delete the folder.

From here on, this is pretty much guessing. Try to download Lightning from AMO and install it. https://addons.mozilla.org/en-US/thunderbird/addon/lightning/

Information about installing extensions: https://support.mozilla.org/kb/installing-addon-thunderbird

If this still doesn't fix it, as a last resort, can you try to create a new profile using profile manager, and then start Thunderbird with the new profile? https://support.mozilla.org/en-US/kb/using-multiple-profiles

Then re-create your account in the new profile.

I’m not sure if installing the add-on from AMO would solve it, but you can try. Doing so would be possible in Safe Mode, but it will be disabled because of that mode and only work when restarting in normal mode, so the issue may persist.

Instead I would delete the extensions.rdf file in the profile folder when Thunderbird is closed, as that contains add-on entries. I’m not entirely sure about this, but recent changes lead to Thunderbird now containing its Calendar/Lightning extension within the Program Files\Mozilla Thunderbird folder (since it is distributed with Thunderbird by default now), so perhaps something was "left over" in the profile folder causing this to happen, in case you had it installed as an add-on previously.

If removing the file does not solve it, creating a new profile might be the best solution, also because you already used MozBackup, even though only one or two files may have been responsible for the original issue. Since the accounts are POP, sent mail may seem to be lost, but a profile backup should still contain them so they are easy to copy back to the new profile afterwards. The same applies to other folders that you may have created, as well as filters, subscriptions and other settings, as well as calendar data.

It is always advised to back up a current profile folder (manually) before creating a new one or doing other things, or just regularly as you may already know. Please also read the profiles article referred to at the top of the article about using multiple profiles mentioned above. For a list of files and folders in the profile, see this page.

Warning: please never use MozBackup again (and to other helpers: please spread the word). I’m not sure if you previously used it for restoring a profile other than today, but as its home page says, it’s no longer actively maintained, and it has caused a lot of issues for users. It has simply not been updated for a while and therefor did not catch up with some file and folder structures like recent Thunderbird versions currently use, so anything can happen.

Safe mode. You've ruled out add-ons and broken layout, so the next most likely possibility, assuming you're not using custom userChrome or a non-default theme, is hardware acceleration. Is it enabled in Tools/Options/Advanced/General?