Sounds like a server setting enforced by your mail provider. IMAP is synchronized so their policies over ride Thunderbird.

Check with your provider if they allow you to opt out of their housekeeping.

spent time on the phone with hostgator and they insist it isn't them. anyone agree that it may be and have an idea on what specific language i can use to get them to figure it out?

also this never happened when i had outlook and i had hostgator then...

Please add the troubleshooting information to your post To find the Troubleshooting information:

• Open Help (or click on three-line-icon and select Help)
• Choose Troubleshooting Information
• Use the button Copy to clipboard to select all. Do not check box "Include account names"!
• Paste this in your post.

Application Basics

   Name: Thunderbird
   Version: 45.4.0
   User Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0
   Profile Folder: Show Folder

             (Local drive)
   Application Build ID: 20160928132736
   Enabled Plugins: about:plugins
   Build Configuration: about:buildconfig
   Memory Use: about:memory

 Mail and News Accounts
   account1:
     INCOMING: account1, , (imap) gator3041.hostgator.com:143, plain, passwordCleartext
     OUTGOING: , mail.hisbeloved.us:26, plain, passwordCleartext, true

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

   account3:
     INCOMING: account3, , (imap) gator3041.hostgator.com:993, SSL, passwordCleartext
     OUTGOING: , gator3041.hostgator.com:26, plain, passwordCleartext, true

   account4:
     INCOMING: account4, , (imap) imap.gmail.com:993, SSL, OAuth2
     OUTGOING: , smtp.gmail.com:465, SSL, OAuth2, true

   account5:
     INCOMING: account5, , (imap) gator3041.hostgator.com:993, SSL, passwordCleartext
     OUTGOING: , gator3041.hostgator.com:26, plain, passwordCleartext, true

   account6:
     INCOMING: account6, , (imap) gator3041.hostgator.com:993, SSL, passwordCleartext
     OUTGOING: , mail.hisbeloved.us:26, plain, passwordCleartext, true

 Crash Reports
   http://crash-stats.mozilla.com/report/index/bp-be29ac8d-adac-4a3b-afc9-c98492161019 (10/19/2016)
   http://crash-stats.mozilla.com/report/index/bp-8952d359-331a-4070-a964-7abe72160620 (6/20/2016)
   http://crash-stats.mozilla.com/report/index/bp-3884749c-1fea-4fb3-8d64-fccaa2160616 (6/16/2016)
   http://crash-stats.mozilla.com/report/index/bp-d3fb82f8-2c87-448e-a93c-eee852160427 (4/27/2016)

 Extensions
   Copy Folder, 2.1, true, copyfolder@crunch.mod
   Email signature for Thunderbird - WiseStamp, 3.14.0, true, wisestamp_tb@wisestamp.com
   Google Calendar Tab, 3.9, true, googlecalendartab@momo
   Lightning, 4.7.4, true, {e2fda1a4-762b-4020-b5ad-a41df1933103}
   Manually sort folders, 1.1.1, true, tbsortfolders@xulforum.org
   MoreFunctionsForAddressBook, 0.7.5, true, {3e17310d-82e8-4a43-bd2f-7c3055bfe589}
   Provider for Google Calendar, 3.1, true, {a62ef8ec-5fdc-40c2-873c-223b8a6925cc}
   Test Pilot for Thunderbird, 1.3.10, true, tbtestpilot@labs.mozilla.com

 Important Modified Preferences

   Name: Value

     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
     dom.max_chrome_script_run_time: 0
     extensions.lastAppVersion: 45.4.0
     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
     mail.openMessageBehavior.version: 1
     mail.winsearch.enable: true
     mail.winsearch.firstRunDone: true
     mail.winsearch.global_reindex_time: 1452530981
     mailnews.database.global.datastore.id: 370e0250-40f9-4238-8f1b-7d745bdd50f
     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…
     network.cookie.prefsMigrated: true
     network.predictor.cleaned-up: true
     places.database.lastMaintenance: 1478013443
     places.history.expiration.transient_current_max_pages: 104858
     plugin.importedState: true
     print.printer_Brother_MFC-J870DW_Printer.print_bgcolor: false
     print.printer_Brother_MFC-J870DW_Printer.print_bgimages: false
     print.printer_Brother_MFC-J870DW_Printer.print_colorspace:
     print.printer_Brother_MFC-J870DW_Printer.print_command:
     print.printer_Brother_MFC-J870DW_Printer.print_downloadfonts: false
     print.printer_Brother_MFC-J870DW_Printer.print_duplex: -437918235
     print.printer_Brother_MFC-J870DW_Printer.print_edge_bottom: 0
     print.printer_Brother_MFC-J870DW_Printer.print_edge_left: 0
     print.printer_Brother_MFC-J870DW_Printer.print_edge_right: 0
     print.printer_Brother_MFC-J870DW_Printer.print_edge_top: 0
     print.printer_Brother_MFC-J870DW_Printer.print_evenpages: true
     print.printer_Brother_MFC-J870DW_Printer.print_footercenter:
     print.printer_Brother_MFC-J870DW_Printer.print_footerleft: &PT
     print.printer_Brother_MFC-J870DW_Printer.print_footerright: &D
     print.printer_Brother_MFC-J870DW_Printer.print_headercenter:
     print.printer_Brother_MFC-J870DW_Printer.print_headerleft: &T
     print.printer_Brother_MFC-J870DW_Printer.print_headerright: &U
     print.printer_Brother_MFC-J870DW_Printer.print_in_color: true
     print.printer_Brother_MFC-J870DW_Printer.print_margin_bottom: 0.5
     print.printer_Brother_MFC-J870DW_Printer.print_margin_left: 0.5
     print.printer_Brother_MFC-J870DW_Printer.print_margin_right: 0.5
     print.printer_Brother_MFC-J870DW_Printer.print_margin_top: 0.5
     print.printer_Brother_MFC-J870DW_Printer.print_oddpages: true
     print.printer_Brother_MFC-J870DW_Printer.print_orientation: 0
     print.printer_Brother_MFC-J870DW_Printer.print_page_delay: 50
     print.printer_Brother_MFC-J870DW_Printer.print_paper_data: 1
     print.printer_Brother_MFC-J870DW_Printer.print_paper_height: 11.00
     print.printer_Brother_MFC-J870DW_Printer.print_paper_name:
     print.printer_Brother_MFC-J870DW_Printer.print_paper_size_type: 0
     print.printer_Brother_MFC-J870DW_Printer.print_paper_size_unit: 0
     print.printer_Brother_MFC-J870DW_Printer.print_paper_width: 8.50
     print.printer_Brother_MFC-J870DW_Printer.print_plex_name:
     print.printer_Brother_MFC-J870DW_Printer.print_resolution: -437918235
     print.printer_Brother_MFC-J870DW_Printer.print_resolution_name:
     print.printer_Brother_MFC-J870DW_Printer.print_reversed: false
     print.printer_Brother_MFC-J870DW_Printer.print_scaling: 1.00
     print.printer_Brother_MFC-J870DW_Printer.print_shrink_to_fit: true
     print.printer_Brother_MFC-J870DW_Printer.print_to_file: false
     print.printer_Brother_MFC-J870DW_Printer.print_unwriteable_margin_bottom: 0
     print.printer_Brother_MFC-J870DW_Printer.print_unwriteable_margin_left: 0
     print.printer_Brother_MFC-J870DW_Printer.print_unwriteable_margin_right: 0
     print.printer_Brother_MFC-J870DW_Printer.print_unwriteable_margin_top: 0

 Graphics

     Adapter Description: Intel(R) HD Graphics 4000
     Vendor ID: 0x8086
     Device ID: 0x0166
     Adapter RAM: Unknown
     Adapter Drivers: igdumdim64 igd10iumd64 igd10iumd64 igdumdim32 igd10iumd32 igd10iumd32
     Driver Version: 10.18.10.4358
     Driver Date: 12-21-2015
     Adapter Description (GPU #2): NVIDIA GeForce 610M
     Vendor ID (GPU #2): 0x10de
     Device ID (GPU #2): 0x1058
     Adapter RAM (GPU #2): 1024
     Adapter Drivers (GPU #2): C:\WINDOWS\System32\DriverStore\FileRepository\nvltwu.inf_amd64_7abb66182eb8ed83\nvd3dumx,C:\WINDOWS\System32\DriverStore\FileRepository\nvltwu.inf_amd64_7abb66182eb8ed83\nvwgf2umx,C:\WINDOWS\System32\DriverStore\FileRepository\nvltwu.inf_amd64_7abb66182eb8ed83\nvwgf2umx,C:\WINDOWS\System32\DriverStore\FileRepository\nvltwu.inf_amd64_7abb66182eb8ed83\nvwgf2umx C:\WINDOWS\System32\DriverStore\FileRepository\nvltwu.inf_amd64_7abb66182eb8ed83\nvd3dum,C:\WINDOWS\System32\DriverStore\FileRepository\nvltwu.inf_amd64_7abb66182eb8ed83\nvwgf2um,C:\WINDOWS\System32\DriverStore\FileRepository\nvltwu.inf_amd64_7abb66182eb8ed83\nvwgf2um,C:\WINDOWS\System32\DriverStore\FileRepository\nvltwu.inf_amd64_7abb66182eb8ed83\nvwgf2um

here is the rest

   Driver Version (GPU #2): 21.21.13.6909
     Driver Date (GPU #2): 8-1-2016
     Direct2D Enabled: false
     DirectWrite Enabled: false (10.0.14393.351)
     ClearType Parameters: Gamma: 2200 Pixel Structure: R ClearType Level: 100 Enhanced Contrast: 50
     WebGL Renderer: Google Inc. -- ANGLE (Intel(R) HD Graphics 4000 Direct3D11 vs_5_0 ps_5_0) -- OpenGL ES 2.0 (ANGLE 2.1.0.316930d51ea9)
     GPU Accelerated Windows: 0

     AzureCanvasBackend: skia
     AzureSkiaAccelerated: 0
     AzureFallbackCanvasBackend: cairo
     AzureContentBackend: cairo

 JavaScript

 Incremental GC: 1

 Accessibility

   Activated: 0
   Prevent Accessibility: 0

 Library Versions

     Expected minimum version
     Version in use

     NSPR
     4.12
     4.12

     NSS

lets just try a workaround.

click one of our hostgator accounts and create a new folder call it newtrash

Choose an account with nothing useful in the trash so we can test things. Select Settings In server settings change the setting when you delete a message to move it to from the trash on the account to move it to newtrash.

I am hopeful that this will bypass the hostgator "trash" in favor of this other folder. It might not. But I figure it is worth a try.

do you mean use one of my other email accounts and do this through thunderbird or go onto hostgator mail and do it directly..

Do it in Thunderbird.

You say this worked OK in Outlook; I bet you used POP then.

No i did not, i have always been imap.

so i tried the new trash idea but thunderbird still puts the trash in the regular trash bin not the new one even tho i directed it to under server settings.

does anyone know if i can get mozilla to respond to these issues directly as i still don't have a resolution

I have never caught any of my numerous accounts doing what you describe. I'm inclined to think it's your provider. We were trying to help someone recently with a hostgator account; he was having trouble with his messages being erroneously classified as spam because of their maverick decision to reject local IP addresses found in the message routing. This experience didn't leave us with a warm feeling about their competence.

OTOH, I only use my Trash/Bin/Deleted folders for messages I don't need any more. I have never understood why folk put into Trash messages that they might want to look at again.

Mozilla has "consciously uncoupled" from Thunderbird and Thunderbird is now run by a Council made up of volunteers. Matt is a member of that Council and so you are about as high up the tree as you can go.

What happens in my business is i sometimes need to retrieve info from a contact that i didn't know i would need..hence why it is in the trash. If i tried to keep everything i thought i might need in the work i do it would create such a huge problem. I will try and respond right to matt i guess then. I just need the right terminology to use with hostgator so that i can figure this out. Do u think the reason my attachments are disappearing is host gator too?

Do you know what mail server they are using? (Message headers - ctrl+u - might help in finding out.) I get empty attachments in an account hosted by outlook.com/office365, but the same messages, copied at server level to a gmail account, are just fine.

This doesn't happen in any of my other accounts. If this is a bug in Thunderbird, it is peculiarly specific.

happy to post that info but when i do the ctrl u on a msg header there is a ton of info there..what specifically are you looking for..this?

by gator3041.hostgator.com with esmtps (TLSv1:ECDHE-RSA-AES256-SHA:256) (Exim 4.87)

Yes, the lines starting with "Received", such as:

Received: from COL004-OMC2S2.hotmail.com [65.55.34.76] by tambamail.co.uk with ESMTP
 (SMTPD-9.03) id A9720230; Wed, 09 Nov 2016 20:39:14 +0000
Received: from EUR03-DB5-obe.outbound.protection.outlook.com ([65.55.34.71]) by COL004-OMC2S2.hotmail.com over TLS secured channel with Microsoft SMTPSVC(7.5.7601.23008);

Wed, 9 Nov 2016 12:38:31 -0800

You'll probably need to send a message to yourself to see the full start-to-finish route.

sent a msg to myself here is what i got

Received: from c-73-37-163-145.hsd1.mn.comcast.net ([73.37.163.145]:50210 helo=[192.168.0.102]) by gator3041.hostgator.com with esmtpa (Exim 4.87) (envelope-from <gretchen@alphapromotesyou.com>) id 1c4r4y-000E62-Kb