diff --git a/koreader-plugin/bookorbit.koplugin/bookorbit_catalog.lua b/koreader-plugin/bookorbit.koplugin/bookorbit_catalog.lua
index 00707a194..6b7f9c7b8 100644
--- a/koreader-plugin/bookorbit.koplugin/bookorbit_catalog.lua
+++ b/koreader-plugin/bookorbit.koplugin/bookorbit_catalog.lua
@@ -832,7 +832,10 @@ function BookOrbitCatalog:showServerError(err)
 end
 
 function BookOrbitCatalog:errorText(err)
-    if isAuthError(err) then
+    local transfer_error = CatalogUtil.transferErrorText(err)
+    if transfer_error then
+        return transfer_error
+    elseif isAuthError(err) then
         return _("BookOrbit login failed. Check your KOReader credentials.")
     elseif type(err) == "number" then
         return T(_("BookOrbit server error (%1)."), err)
diff --git a/koreader-plugin/bookorbit.koplugin/bookorbit_catalog_util.lua b/koreader-plugin/bookorbit.koplugin/bookorbit_catalog_util.lua
index 4698b8894..f71aab999 100644
--- a/koreader-plugin/bookorbit.koplugin/bookorbit_catalog_util.lua
+++ b/koreader-plugin/bookorbit.koplugin/bookorbit_catalog_util.lua
@@ -386,6 +386,15 @@ function CatalogUtil.safeFilenameBase(detail)
     return base
 end
 
+function CatalogUtil.transferErrorText(err)
+    if err == "unsafe_destination" then
+        return _("The download destination is outside the selected folder.")
+    elseif err == "temp_dir_failed" then
+        return _("Could not create a temporary download folder in the selected folder.")
+    end
+    return nil
+end
+
 function CatalogUtil.coverLabel(book)
     local lines = {}
     local title = book and book.title or _("Untitled")
diff --git a/koreader-plugin/bookorbit.koplugin/bookorbit_download_transfer.lua b/koreader-plugin/bookorbit.koplugin/bookorbit_download_transfer.lua
index 7b58bc60d..365394e34 100644
--- a/koreader-plugin/bookorbit.koplugin/bookorbit_download_transfer.lua
+++ b/koreader-plugin/bookorbit.koplugin/bookorbit_download_transfer.lua
@@ -31,11 +31,14 @@ Transfer.TEMP_DIR_NAME = TEMP_DIR_NAME
 Transfer.POLL_INTERVAL = POLL_INTERVAL
 
 local function normalize(path)
-    return tostring(path or ""):gsub("\\", "/"):gsub("/+", "/"):gsub("/$", "")
+    local normalized = tostring(path or ""):gsub("\\", "/"):gsub("/+", "/")
+    if normalized == "/" then return normalized end
+    return normalized:gsub("/$", "")
 end
 
 function Transfer.tempDir(root)
-    return normalize(root) .. "/" .. TEMP_DIR_NAME
+    local normalized_root = normalize(root)
+    return (normalized_root ~= "/" and normalized_root or "") .. "/" .. TEMP_DIR_NAME
 end
 
 function Transfer.ensureTempDir(root)
@@ -52,7 +55,11 @@ function Transfer.isInsideRoot(root, path)
     local normalized_root = normalize(root)
     local normalized_path = normalize(path)
     if normalized_root == "" or normalized_path == "" then return false end
-    if normalized_path:sub(1, #normalized_root + 1) ~= normalized_root .. "/" then return false end
+    if normalized_root == "/" then
+        if normalized_path == "/" or normalized_path:sub(1, 1) ~= "/" then return false end
+    elseif normalized_path:sub(1, #normalized_root + 1) ~= normalized_root .. "/" then
+        return false
+    end
     for segment in normalized_path:gmatch("[^/]+") do
         if segment == ".." then return false end
     end
diff --git a/koreader-plugin/bookorbit.koplugin/main.lua b/koreader-plugin/bookorbit.koplugin/main.lua
index e63a5dc45..ffccf4f6c 100644
--- a/koreader-plugin/bookorbit.koplugin/main.lua
+++ b/koreader-plugin/bookorbit.koplugin/main.lua
@@ -48,7 +48,7 @@ local BookOrbitProgressSync = require("bookorbit_progress_sync")
 local BookOrbitSweep = require("bookorbit_sweep")
 local BookOrbitUpdater = require("bookorbit_updater")
 
-local PLUGIN_VERSION = "1.5.0"
+local PLUGIN_VERSION = "1.5.1"
 
 local SYNC_STRATEGY = {
     PROMPT = 1,
diff --git a/koreader-plugin/spec/bookorbit_catalog_transfer_error_test.lua b/koreader-plugin/spec/bookorbit_catalog_transfer_error_test.lua
new file mode 100644
index 000000000..a5660f5b6
--- /dev/null
+++ b/koreader-plugin/spec/bookorbit_catalog_transfer_error_test.lua
@@ -0,0 +1,42 @@
+local function identity(value)
+    return value
+end
+
+package.loaded["gettext"] = identity
+package.loaded["document/documentregistry"] = {
+    hasProvider = function()
+        return true
+    end,
+}
+package.loaded["util"] = {
+    fixUtf8 = identity,
+}
+package.loaded["ffi/util"] = {
+    template = function(value)
+        return value
+    end,
+}
+
+package.path = "koreader-plugin/bookorbit.koplugin/?.lua;" .. package.path
+
+local CatalogUtil = require("bookorbit_catalog_util")
+
+local function assertEqual(actual, expected, label)
+    if actual ~= expected then
+        error(string.format("%s: expected %s, got %s", label, tostring(expected), tostring(actual)))
+    end
+end
+
+assertEqual(
+    CatalogUtil.transferErrorText("unsafe_destination"),
+    "The download destination is outside the selected folder.",
+    "unsafe destinations are reported as local path failures"
+)
+assertEqual(
+    CatalogUtil.transferErrorText("temp_dir_failed"),
+    "Could not create a temporary download folder in the selected folder.",
+    "temporary directory failures are reported as local filesystem failures"
+)
+assertEqual(CatalogUtil.transferErrorText("network_error"), nil, "network errors keep the existing connection message")
+
+print("bookorbit_catalog_transfer_error_test.lua: ok")
diff --git a/koreader-plugin/spec/bookorbit_download_transfer_test.lua b/koreader-plugin/spec/bookorbit_download_transfer_test.lua
index 235b2d2ea..1ba1e9788 100644
--- a/koreader-plugin/spec/bookorbit_download_transfer_test.lua
+++ b/koreader-plugin/spec/bookorbit_download_transfer_test.lua
@@ -10,7 +10,10 @@ package.loaded["ui/uimanager"] = {
     end,
 }
 
-local directories = { ["/downloads/.bookorbit-tmp"] = true }
+local directories = {
+    ["/.bookorbit-tmp"] = true,
+    ["/downloads/.bookorbit-tmp"] = true,
+}
 local files = {}
 local now = 1000
 package.loaded["libs/libkoreader-lfs"] = {
@@ -66,10 +69,16 @@ end
 -- Destination containment is checked before anything is written and again
 -- before the publishing rename.
 assertEqual(Transfer.isInsideRoot("/downloads", "/downloads/Books/a.epub"), true, "a path under the root is authorized")
+assertEqual(Transfer.isInsideRoot("/downloads", "/downloads/The Shards.epub"), true,
+    "a file directly under the download root is authorized")
 assertEqual(Transfer.isInsideRoot("/downloads", "/elsewhere/a.epub"), false, "a path outside the root is rejected")
 assertEqual(Transfer.isInsideRoot("/downloads", "/downloads/../etc/passwd"), false, "traversal is rejected")
 assertEqual(Transfer.isInsideRoot("/downloads", "/downloads"), false, "the root itself is not a destination")
 assertEqual(Transfer.tempDir("/downloads"), "/downloads/.bookorbit-tmp", "temporaries live under the destination root")
+assertEqual(Transfer.isInsideRoot("/", "/The Shards.epub"), true, "the filesystem root supports a direct book destination")
+assertEqual(Transfer.isInsideRoot("/", "/Standalone/The Shards.epub"), true, "the filesystem root supports nested destinations")
+assertEqual(Transfer.isInsideRoot("/", "/../etc/passwd"), false, "the filesystem root still rejects traversal")
+assertEqual(Transfer.tempDir("/"), "/.bookorbit-tmp", "the filesystem root gets one temporary directory separator")
 
 -- Leftovers from a killed run are removed, and the sweep stays bounded.
 files["/downloads/.bookorbit-tmp/bo_1_1.part"] = { size = 10, modified = 1 }
@@ -141,6 +150,25 @@ runScheduled()
 assertEqual(#scheduled, 0, "a poll that fires after completion does not reschedule itself")
 assertEqual(#observed, 1, "no progress is reported once the transfer returned")
 
+-- A user-selected filesystem root used to normalize to an empty string and
+-- reject the destination before perform could start the HTTP request.
+local root_request_started = false
+local root_completed = Transfer.run{
+    root = "/",
+    destination = "/The Shards.epub",
+    generation = 5,
+    expected_bytes = 2089926,
+    is_current = function() return true end,
+    perform = function(download_opts)
+        root_request_started = true
+        files[download_opts.temp_path] = { size = 2089926, modified = now }
+        return { temp_path = download_opts.temp_path, bytes = 2089926 }
+    end,
+}
+assertEqual(root_request_started, true, "the reported book reaches the HTTP transfer callback")
+assertEqual(root_completed, true, "the reported book publishes under a filesystem-root download folder")
+assertEqual(files["/The Shards.epub"] ~= nil, true, "the reported book is published at the requested destination")
+
 -- A cancelled generation discards a late child result instead of publishing it.
 renames = {}
 removed = {}