Clearly your outgoing server (SMTP settings are not correct. Otherwise the outgoing server would not be replying that is is an incoming server (IMAP).

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.

Thank you not sure if I am doing this right for you.

Troubleshooting Information This page contains technical information that might be useful when you're trying to solve a problem. If you are looking for answers to common questions about Thunderbird, check out our support web site. Include account names (possibly identifying information) Application Basics Name Thunderbird Version 52.8.0 User Agent Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:52.0) Gecko/20100101 Thunderbird/52.8.0 Profile Folder Application Build ID 20180516145259 Enabled Plugins about:plugins Build Configuration about:buildconfig Memory Use about:memory Profiles about:profiles Mail and News Accounts ID Incoming server Outgoing servers Name Connection security Authentication method Name Connection security Authentication method Default? account2 (none) Local Folders None Normal password account3 (imap) 5ctw-zg22.accessdomain.com:993 SSL/TLS Normal password 5ctw-zg22.accessdomain.com:993 SSL/TLS Normal password true Crash Reports Report ID Submitted bp-8b2ef5c1-2814-4934-a22a-023d20180613 13/06/2018

All Crash Reports Extensions Name Version Enabled ID Lightning 5.4.8 true {e2fda1a4-762b-4020-b5ad-a41df1933103} Important Modified Preferences Name Value browser.cache.disk.capacity 358400 browser.cache.disk.filesystem_reported 1 extensions.lastAppVersion 52.8.0 mail.openMessageBehavior.version 1 mail.spotlight.firstRunDone true mailnews.database.global.datastore.id b5ac72a2-1a33-ce47-b1b3-ff5cd418e49 mailnews.database.global.views.conversation.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 1529611181 places.history.expiration.transient_current_max_pages 122334 print.macosx.pagesetup-2 PD94bWwgdmVyc2lvbj0iMS4wIiBlbmNvZGluZz0iVVRGLTgiPz4KPCFET0NUWVBFIHBsaXN0IFBVQkxJQyAiLS8vQXBwbGUvL0RURCBQTElTVCAxLjAvL0VO… security.disable_button.openCertManager false security.disable_button.openDeviceManager false security.sandbox.content.tempDirSuffix {00c5072a-6a60-b246-9b88-0f7cbf060687} Graphics GPU #1 Vendor ID 0x8086 Device ID 0x591b Features WebGL Renderer ATI Technologies Inc. -- AMD Radeon Pro 560 OpenGL Engine -- 2.1 ATI-1.60.26 AzureCanvasBackend skia AzureCanvasAccelerated 0 AzureFallbackCanvasBackend none AzureContentBackend skia TileHeight 1024 TileWidth 1024 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 3.28.6 3.28.6 NSS Util 3.28.6 3.28.6 NSS SSL 3.28.6 3.28.6 NSS S/MIME 3.28.6 3.28.6

the server names shown in your troubleshooting information do not bear an resemblance to the information on the media temple web site.

Did you use their tool? https://mediatemple.net/help/mail/mailconfig/