Application Basics

   Name: Thunderbird
   Version: 52.1.1
   User Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.1.1
   Profile Folder: Open Folder

             (Local drive)
   Application Build ID: 20170509142926
   Enabled Plugins: about:plugins
   Build Configuration: about:buildconfig
   Memory Use: about:memory
   Profiles: about:profiles

 Mail and News Accounts
   account1:
     INCOMING: account1, , (imap) imap.gmail.com:993, SSL, OAuth2
     OUTGOING: , smtp.gmail.com:465, SSL, OAuth2, true

   account2:
     INCOMING: account2, , (none) Local Folders, plain, passwordCleartext

   account3:
     INCOMING: account3, , (imap) mobile.charter.net:993, SSL, passwordCleartext
     OUTGOING: , mobile.charter.net:587, SSL, passwordCleartext, true

 Crash Reports

 Extensions
   gContactSync, 2.0.12, true, [email protected]
   Google Tasks Sync, 0.5.3, true, [email protected]
   Lightning, 5.4.1.1, true, {e2fda1a4-762b-4020-b5ad-a41df1933103}
   Lightning Calendar Tabs, 1.5, true, [email protected]
   Provider for Google Calendar, 3.3, true, {a62ef8ec-5fdc-40c2-873c-223b8a6925cc}

 Important Modified Preferences

   Name: Value

     accessibility.lastLoadDate: 1495214025
     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
     dom.apps.reset-permissions: true
     extensions.lastAppVersion: 52.1.1
     font.internaluseonly.changed: true
     font.name.monospace.el: 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.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.x-cyrillic: Cambria
     font.name.serif.x-unicode: Cambria
     font.name.serif.x-western: Cambria
     font.size.fixed.el: 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.x-cyrillic: 17
     font.size.variable.x-unicode: 17
     font.size.variable.x-western: 17
     mail.openMessageBehavior.version: 1
     mail.winsearch.firstRunDone: true
     mailnews.database.global.datastore.id: bd72bf49-5948-41ac-a0bd-6118995ca73
     mailnews.database.global.views.conversation.columns: {"threadCol":{"visible":true,"ordinal":"1"},"flaggedCol":{"visible":true,"ordinal":"3"},"attachmentCol":{"visible":false…
     mailnews.database.global.views.global.columns: {"threadCol":{"visible":true,"ordinal":"1"},"flaggedCol":{"visible":true,"ordinal":"3"},"attachmentCol":{"visible":false…
     media.gmp.storage.version.observed: 1
     network.cookie.prefsMigrated: true
     network.predictor.cleaned-up: true
     places.database.lastMaintenance: 1495591383
     places.history.expiration.transient_current_max_pages: 122334
     plugin.importedState: true
     security.sandbox.content.tempDirSuffix: {836f9174-8c76-47a4-8bc6-6048edb6e330}

 Graphics

     GPU #1
     Description: Intel(R) HD Graphics 4000
     Vendor ID: 0x8086
     Device ID: 0x0166
     RAM: Unknown
     Drivers: igdumdim64 igd10iumd64 igd10iumd64 igdumdim32 igd10iumd32 igd10iumd32
     Driver Version: 10.18.10.4425
     Driver Date: 4-4-2016

     Features
     Direct2D: false
     DirectWrite: true (10.0.16188.1000)
     WebGL Renderer: Google Inc. -- ANGLE (Intel(R) HD Graphics 4000 Direct3D9Ex vs_3_0 ps_3_0) -- OpenGL ES 2.0 (ANGLE 2.1.0.2a250c8a0e15)

     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
     3.28.4
     3.28.4

     NSS Util
     3.28.4
     3.28.4

     NSS SSL
     3.28.4
     3.28.4

     NSS S/MIME
     3.28.4
     3.28.4

I am running Windows 10 and I had to do a system restore when my computer got funky today. After everything was restored, Thunderbird lost the calendar tab completely. I am pasting the Thunderbird information below and a screenshot of the missing tab. I sync the calendar with Google Calendar, and I really, really need it back. I have tried opening Thunderbird in safe mode, I have downloaded it and reinstalled it, I have deleted it completely, and reinstalled it, to no avail. Application Basics Name: Thunderbird Version: 52.1.1 User Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.1.1 Profile Folder: Open Folder (Local drive) Application Build ID: 20170509142926 Enabled Plugins: about:plugins Build Configuration: about:buildconfig Memory Use: about:memory Profiles: about:profiles Mail and News Accounts account1: INCOMING: account1, , (imap) imap.gmail.com:993, SSL, OAuth2 OUTGOING: , smtp.gmail.com:465, SSL, OAuth2, true account2: INCOMING: account2, , (none) Local Folders, plain, passwordCleartext account3: INCOMING: account3, , (imap) mobile.charter.net:993, SSL, passwordCleartext OUTGOING: , mobile.charter.net:587, SSL, passwordCleartext, true Crash Reports Extensions gContactSync, 2.0.12, true, [email protected] Google Tasks Sync, 0.5.3, true, [email protected] Lightning, 5.4.1.1, true, {e2fda1a4-762b-4020-b5ad-a41df1933103} Lightning Calendar Tabs, 1.5, true, [email protected] Provider for Google Calendar, 3.3, true, {a62ef8ec-5fdc-40c2-873c-223b8a6925cc} Important Modified Preferences Name: Value accessibility.lastLoadDate: 1495214025 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 dom.apps.reset-permissions: true extensions.lastAppVersion: 52.1.1 font.internaluseonly.changed: true font.name.monospace.el: 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.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.x-cyrillic: Cambria font.name.serif.x-unicode: Cambria font.name.serif.x-western: Cambria font.size.fixed.el: 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.x-cyrillic: 17 font.size.variable.x-unicode: 17 font.size.variable.x-western: 17 mail.openMessageBehavior.version: 1 mail.winsearch.firstRunDone: true mailnews.database.global.datastore.id: bd72bf49-5948-41ac-a0bd-6118995ca73 mailnews.database.global.views.conversation.columns: {"threadCol":{"visible":true,"ordinal":"1"},"flaggedCol":{"visible":true,"ordinal":"3"},"attachmentCol":{"visible":false… mailnews.database.global.views.global.columns: {"threadCol":{"visible":true,"ordinal":"1"},"flaggedCol":{"visible":true,"ordinal":"3"},"attachmentCol":{"visible":false… media.gmp.storage.version.observed: 1 network.cookie.prefsMigrated: true network.predictor.cleaned-up: true places.database.lastMaintenance: 1495591383 places.history.expiration.transient_current_max_pages: 122334 plugin.importedState: true security.sandbox.content.tempDirSuffix: {836f9174-8c76-47a4-8bc6-6048edb6e330} Graphics GPU #1 Description: Intel(R) HD Graphics 4000 Vendor ID: 0x8086 Device ID: 0x0166 RAM: Unknown Drivers: igdumdim64 igd10iumd64 igd10iumd64 igdumdim32 igd10iumd32 igd10iumd32 Driver Version: 10.18.10.4425 Driver Date: 4-4-2016 Features Direct2D: false DirectWrite: true (10.0.16188.1000) WebGL Renderer: Google Inc. -- ANGLE (Intel(R) HD Graphics 4000 Direct3D9Ex vs_3_0 ps_3_0) -- OpenGL ES 2.0 (ANGLE 2.1.0.2a250c8a0e15) 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 3.28.4 3.28.4 NSS Util 3.28.4 3.28.4 NSS SSL 3.28.4 3.28.4 NSS S/MIME 3.28.4 3.28.4