I had reinstalled the app already (though I’m not sure I did a full uninstall first) but in the end I had some spare time and so I transferred the files from one external drive to another then reformatted the drive so it would trigger a new request to backup. This worked. As a suggestion, it seems like there should be some manual way to tell Dropbox to backup a drive after originally indicating not to and not to ask again.
Thanks!","body@stripHtml({\"removeProcessingText\":true,\"removeSpoilerMarkup\":true,\"removeTocMarkup\":true,\"truncateLength\":200})@stringLength":"203","postTime":"2021-08-14T06:55:24.225-07:00","lastPublishTime":"2021-08-14T06:55:24.225-07:00","images":{"__typename":"AssociatedImageConnection","edges":[],"totalCount":0,"pageInfo":{"__typename":"PageInfo","hasNextPage":false,"endCursor":null,"hasPreviousPage":false,"startCursor":null}},"attachments":{"__typename":"AttachmentConnection","pageInfo":{"__typename":"PageInfo","hasNextPage":false,"endCursor":null,"hasPreviousPage":false,"startCursor":null},"edges":[]},"solution":true,"metrics":{"__typename":"MessageMetrics","views":4652},"placeholder":false,"originalMessageForPlaceholder":null,"videos":{"__typename":"VideoConnection","edges":[],"totalCount":0,"pageInfo":{"__typename":"PageInfo","hasNextPage":false,"endCursor":null,"hasPreviousPage":false,"startCursor":null}},"isEscalated":null,"entityType":"FORUM_REPLY","eventPath":"category:101001000/category:English/community:mxpez29397board:101001014/message:538760/message:539299","customFields":[]},"User:user:1428660":{"__typename":"User","id":"user:1428660","uid":1428660,"login":"MarkRM","deleted":false,"avatar":{"__typename":"UserAvatar","url":"https://www.dropboxforum.com/t5/s/mxpez29397/m_assets/avatars/default/avatar-8.svg?time=0"},"rank":{"__ref":"Rank:rank:44"},"email":"","messagesCount":4,"biography":null,"topicsCount":0,"kudosReceivedCount":6,"kudosGivenCount":1,"kudosWeight":1,"registrationData":{"__typename":"RegistrationData","status":null,"registrationTime":"2021-04-01T21:44:33.738-07:00","confirmEmailStatus":null},"followersCount":null,"solutionsCount":1},"ModerationData:moderation_data:558372":{"__typename":"ModerationData","id":"moderation_data:558372","status":"APPROVED","rejectReason":null,"isReportedAbuse":false,"rejectUser":null,"rejectTime":null,"rejectActorType":"member"},"Revision:revision:558372_1":{"__typename":"Revision","id":"revision:558372_1","lastEditTime":"2021-11-17T21:39:19.636-08:00"},"QueryVariables:ReplyList:message:558372:1":{"__typename":"QueryVariables","id":"ReplyList:message:558372:1","value":{"id":"message:558372","first":10,"sorts":{"postTime":{"direction":"ASC"}},"repliesFirst":3,"repliesFirstDepthThree":1,"repliesSorts":{"postTime":{"direction":"ASC"}},"useAvatar":true,"useAuthorLogin":true,"useAuthorRank":true,"useBody":true,"useKudosCount":true,"useTimeToRead":false,"useMedia":false,"useReadOnlyIcon":false,"useRepliesCount":true,"useSearchSnippet":false,"useAcceptedSolutionButton":true,"useSolvedBadge":false,"useAttachments":false,"attachmentsFirst":5,"useTags":false,"useNodeAncestors":false,"useUserHoverCard":false,"useNodeHoverCard":false,"useModerationStatus":true,"usePreviewSubjectModal":false,"useMessageStatus":true}},"CachedAsset:text:en_US-components/community/NavbarDropdownToggle-1744039679000":{"__typename":"CachedAsset","id":"text:en_US-components/community/NavbarDropdownToggle-1744039679000","value":{"ariaLabelClosed":"Press the down arrow to open the menu"},"localOverride":false},"CachedAsset:text:en_US-components/customComponent/CustomComponent-1744039679000":{"__typename":"CachedAsset","id":"text:en_US-components/customComponent/CustomComponent-1744039679000","value":{"errorMessage":"Error rendering component id: {customComponentId}","bannerTitle":"Video provider requires cookies to play the video. Accept to continue or {url} it directly on the provider's site.","buttonTitle":"Accept","urlText":"watch"},"localOverride":false},"CachedAsset:text:en_US-shared/client/components/users/UserAvatar-1744039679000":{"__typename":"CachedAsset","id":"text:en_US-shared/client/components/users/UserAvatar-1744039679000","value":{"altText":"{login}'s avatar","altTextGeneric":"User's avatar"},"localOverride":false},"CachedAsset:text:en_US-shared/client/components/ranks/UserRankLabel-1744039679000":{"__typename":"CachedAsset","id":"text:en_US-shared/client/components/ranks/UserRankLabel-1744039679000","value":{"altTitle":"Icon for {rankName} rank"},"localOverride":false},"CachedAsset:text:en_US-components/tags/TagView/TagViewChip-1744039679000":{"__typename":"CachedAsset","id":"text:en_US-components/tags/TagView/TagViewChip-1744039679000","value":{"tagLabelName":"Tag name {tagName}"},"localOverride":false},"CachedAsset:text:en_US-components/messages/AcceptedSolutionButton-1744039679000":{"__typename":"CachedAsset","id":"text:en_US-components/messages/AcceptedSolutionButton-1744039679000","value":{"accept":"Mark as Solution","accepted":"Marked as Solution","errorHeader":"Error!","errorAdd":"There was an error marking as solution.","errorRemove":"There was an error unmarking as solution.","solved":"Solved","topicAlreadySolvedErrorTitle":"Solution Already Exists","topicAlreadySolvedErrorDesc":"Refresh the browser to view the existing solution"},"localOverride":false},"CachedAsset:text:en_US-components/messages/ThreadedReplyList-1744039679000":{"__typename":"CachedAsset","id":"text:en_US-components/messages/ThreadedReplyList-1744039679000","value":{"title":"{count, plural, one{# Reply} other{# Replies}}","title@board:BLOG":"{count, plural, one{# Comment} other{# Comments}}","title@board:TKB":"{count, plural, one{# Comment} other{# Comments}}","title@board:IDEA":"{count, plural, one{# Comment} other{# Comments}}","title@board:OCCASION":"{count, plural, one{# Comment} other{# Comments}}","noRepliesTitle":"No Replies","noRepliesTitle@board:BLOG":"No Comments","noRepliesTitle@board:TKB":"No Comments","noRepliesTitle@board:IDEA":"No Comments","noRepliesTitle@board:OCCASION":"No Comments","noRepliesDescription":"Be the first to reply","noRepliesDescription@board:BLOG":"Be the first to comment","noRepliesDescription@board:TKB":"Be the first to comment","noRepliesDescription@board:IDEA":"Be the first to comment","noRepliesDescription@board:OCCASION":"Be the first to comment","messageReadOnlyAlert:BLOG":"Comments have been turned off for this post","messageReadOnlyAlert:TKB":"Comments have been turned off for this article","messageReadOnlyAlert:IDEA":"Comments have been turned off for this idea","messageReadOnlyAlert:FORUM":"Replies have been turned off for this discussion","messageReadOnlyAlert:OCCASION":"Comments have been turned off for this event"},"localOverride":false},"CachedAsset:text:en_US-components/nodes/NodeView/NodeViewCard-1744039679000":{"__typename":"CachedAsset","id":"text:en_US-components/nodes/NodeView/NodeViewCard-1744039679000","value":{"title":"{nodeTitle} ","creationDate":"Created: {creationDate}","ownedBy":"Owned by: {owners}{text}","showOwnerListText":", and {ownersCount} more","unreadCount":"{count} unread","nodeViewDrawerBtn":"Node view drawer for {place}","drawerActionTooltip":"Show category children"},"localOverride":false},"CachedAsset:text:en_US-components/messages/MessageView/MessageViewInline-1744039679000":{"__typename":"CachedAsset","id":"text:en_US-components/messages/MessageView/MessageViewInline-1744039679000","value":{"bylineAuthor":"{bylineAuthor}","bylineBoard":"{bylineBoard}","anonymous":"Anonymous","place":"Place {bylineBoard}","gotoParent":"Go to parent {name}"},"localOverride":false},"CachedAsset:text:en_US-shared/client/components/common/Pager/PagerLoadMore-1744039679000":{"__typename":"CachedAsset","id":"text:en_US-shared/client/components/common/Pager/PagerLoadMore-1744039679000","value":{"loadMore":"Show More"},"localOverride":false},"CachedAsset:text:en_US-shared/client/components/nodes/NodeAvatar-1744039679000":{"__typename":"CachedAsset","id":"text:en_US-shared/client/components/nodes/NodeAvatar-1744039679000","value":{"altTitle":"Node avatar for {nodeTitle}"},"localOverride":false},"CachedAsset:text:en_US-shared/client/components/nodes/NodeDescription-1744039679000":{"__typename":"CachedAsset","id":"text:en_US-shared/client/components/nodes/NodeDescription-1744039679000","value":{"description":"{description}"},"localOverride":false},"CachedAsset:text:en_US-shared/client/components/nodes/NodeIcon-1744039679000":{"__typename":"CachedAsset","id":"text:en_US-shared/client/components/nodes/NodeIcon-1744039679000","value":{"contentType":"Content Type {style, select, FORUM {Forum} BLOG {Blog} TKB {Knowledge Base} IDEA {Ideas} OCCASION {Events} other {}} icon"},"localOverride":false}}}},"page":"/forums/ForumMessagePage/ForumMessagePage","query":{"boardId":"101001014","messageSubject":"i-told-dropbox-to-not-backup-an-external-drive-now-ive-changed-my-mind","messageId":"538760","replyId":"558372"},"buildId":"FP3zsFp6DJl70wDujOvtu","runtimeConfig":{"buildInformationVisible":false,"logLevelApp":"info","logLevelMetrics":"info","openTelemetryClientEnabled":false,"openTelemetryConfigName":"dropbox","openTelemetryServiceVersion":"25.3.0","openTelemetryUniverse":"prod","openTelemetryCollector":"http://localhost:4318","openTelemetryRouteChangeAllowedTime":"5000","apolloDevToolsEnabled":false,"inboxMuteWipFeatureEnabled":false},"isFallback":false,"isExperimentalCompile":false,"dynamicIds":["./components/seo/QAPageSchema/QAPageSchema.tsx","./components/community/Navbar/NavbarWidget.tsx","./components/customComponent/CustomComponent/CustomComponent.tsx","./components/community/Breadcrumb/BreadcrumbWidget.tsx","./components/messages/TopicWithThreadedReplyListWidget/TopicWithThreadedReplyListWidget.tsx","./components/messages/MessageView/MessageViewStandard/MessageViewStandard.tsx","./components/nodes/NodeActionButtonWidget/NodeActionButtonWidget.tsx","./components/nodes/NodeInformationWidget/NodeInformationWidget.tsx","./components/messages/RelatedContentWidget/RelatedContentWidget.tsx","./components/messages/MessageListForNodeByRecentActivityWidget/MessageListForNodeByRecentActivityWidget.tsx","./components/customComponent/CustomComponentContent/HtmlContent.tsx","../shared/client/components/common/List/UnwrappedList/UnwrappedList.tsx","./components/tags/TagView/TagView.tsx","./components/tags/TagView/TagViewChip/TagViewChip.tsx","../shared/client/components/common/List/UnstyledList/UnstyledList.tsx","./components/messages/MessageView/MessageView.tsx","./components/nodes/NodeView/NodeView.tsx","./components/nodes/NodeView/NodeViewCard/NodeViewCard.tsx","./components/messages/MessageView/MessageViewInline/MessageViewInline.tsx","../shared/client/components/common/Pager/PagerLoadMore/PagerLoadMore.tsx","./components/customComponent/CustomComponentContent/TemplateContent.tsx","./components/customComponent/CustomComponentContent/CustomComponentScripts.tsx"],"appGip":true,"scriptLoader":[]}