Seriously I doubt either case is correct.

Is the account IMAP or POP?

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Supplemental info:

Application Basics

Name Thunderbird Version 38.1.0 User Agent Mozilla/5.0 (Windows NT 6.1; rv:38.0) Gecko/20100101 Thunderbird/38.1.0 Profile Folder Show Folder (Local drive) Application Build ID 20150707103124 Enabled Plugins about:plugins Build Configuration about:buildconfig Memory Use about:memory Mail and News Accounts ID Incoming server Outgoing servers Name Connection security Authentication method Name Connection security Authentication method Default? account2 (none) Local Folders plain passwordCleartext account3 (pop3) pop.earthlink.net:110 plain passwordEncrypted smtpauth.earthlink.net:587 alwaysSTARTTLS passwordEncrypted true Crash Reports Report ID Submitted Extensions Name Version Enabled ID Adblock Plus 2.6.10 true {d10d0bf8-f5b5-c8b4-a8b2-2b9879e08c5d} Lightning 4.0.1.2 true {e2fda1a4-762b-4020-b5ad-a41df1933103} Important Modified Preferences Name Value 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 38.1.0 font.internaluseonly.changed true 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 Kalinga 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 1 mail.openMessageBehavior.version 1 mail.winsearch.firstRunDone true mailnews.database.global.datastore.id 66005fc8-8928-4eef-8334-e63dc237b7f mailnews.database.global.views.conversation.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 1438467830 places.history.expiration.transient_current_max_pages 93900 plugin.importedState true plugin.state.flash 0 plugin.state.npctrl 0 plugin.state.npdeployjava 0 plugin.state.npezffpi 0 plugin.state.npgeplugin 0 plugin.state.npgoogleupdate 0 plugin.state.nppdf 0 print.printer_Canon_MG5200_series_Printer.print_bgcolor false print.printer_Canon_MG5200_series_Printer.print_bgimages false print.printer_Canon_MG5200_series_Printer.print_colorspace print.printer_Canon_MG5200_series_Printer.print_command print.printer_Canon_MG5200_series_Printer.print_downloadfonts false print.printer_Canon_MG5200_series_Printer.print_duplex 0 print.printer_Canon_MG5200_series_Printer.print_edge_bottom 0 print.printer_Canon_MG5200_series_Printer.print_edge_left 0 print.printer_Canon_MG5200_series_Printer.print_edge_right 0 print.printer_Canon_MG5200_series_Printer.print_edge_top 0 print.printer_Canon_MG5200_series_Printer.print_evenpages true print.printer_Canon_MG5200_series_Printer.print_footercenter print.printer_Canon_MG5200_series_Printer.print_footerleft &PT print.printer_Canon_MG5200_series_Printer.print_footerright &D print.printer_Canon_MG5200_series_Printer.print_headercenter print.printer_Canon_MG5200_series_Printer.print_headerleft print.printer_Canon_MG5200_series_Printer.print_headerright print.printer_Canon_MG5200_series_Printer.print_in_color true print.printer_Canon_MG5200_series_Printer.print_margin_bottom 0.300000011920929 print.printer_Canon_MG5200_series_Printer.print_margin_left 0.200000002980232 print.printer_Canon_MG5200_series_Printer.print_margin_right 0.200000002980232 print.printer_Canon_MG5200_series_Printer.print_margin_top 0.300000011920929 print.printer_Canon_MG5200_series_Printer.print_oddpages true print.printer_Canon_MG5200_series_Printer.print_orientation 0 print.printer_Canon_MG5200_series_Printer.print_page_delay 50 print.printer_Canon_MG5200_series_Printer.print_paper_data 1 print.printer_Canon_MG5200_series_Printer.print_paper_height 11.00 print.printer_Canon_MG5200_series_Printer.print_paper_name print.printer_Canon_MG5200_series_Printer.print_paper_size_type 0 print.printer_Canon_MG5200_series_Printer.print_paper_size_unit 0 print.printer_Canon_MG5200_series_Printer.print_paper_width 8.50 print.printer_Canon_MG5200_series_Printer.print_plex_name print.printer_Canon_MG5200_series_Printer.print_resolution 0 print.printer_Canon_MG5200_series_Printer.print_resolution_name print.printer_Canon_MG5200_series_Printer.print_reversed false print.printer_Canon_MG5200_series_Printer.print_scaling 0.80 print.printer_Canon_MG5200_series_Printer.print_shrink_to_fit false print.printer_Canon_MG5200_series_Printer.print_to_file false print.printer_Canon_MG5200_series_Printer.print_unwriteable_margin_bottom 0 print.printer_Canon_MG5200_series_Printer.print_unwriteable_margin_left 0 print.printer_Canon_MG5200_series_Printer.print_unwriteable_margin_right 0 print.printer_Canon_MG5200_series_Printer.print_unwriteable_margin_top 0 privacy.donottrackheader.enabled true Graphics Adapter Description NVIDIA Quadro NVS 135M Vendor ID 0x10de Device ID 0x042b Adapter RAM 128 Adapter Drivers nvd3dum nvwgf2um,nvwgf2um Driver Version 9.18.13.3311 Driver Date 4-29-2014 Direct2D Enabled true DirectWrite Enabled true (6.2.9200.17292) ClearType Parameters Gamma: 2200 Pixel Structure: R ClearType Level: 50 Enhanced Contrast: 300 WebGL Renderer false GPU Accelerated Windows 1/1 Direct3D 11 AzureCanvasBackend direct2d 1.1 AzureSkiaAccelerated 0 AzureFallbackCanvasBackend cairo AzureContentBackend direct2d 1.1 JavaScript Incremental GC 1 Accessibility Activated 0 Prevent Accessibility 0 Library Versions Expected minimum version Version in use NSPR 4.10.8 4.10.8 NSS 3.19.2 Basic ECC 3.19.2 Basic ECC NSS Util 3.19.2 3.19.2 NSS SSL 3.19.2 Basic ECC 3.19.2 Basic ECC NSS S/MIME 3.19.2 Basic ECC 3.19.2 Basic ECC

...and then ???