diff --git a/R/DataMart.R b/R/DataMart.R
index 6cb7bf0..85776eb 100644
--- a/R/DataMart.R
+++ b/R/DataMart.R
@@ -31,7 +31,7 @@ QFileExists <- function(filename, show.warning = TRUE, company.token = NA, docum
     if (is.null(res$status_code) || res$status_code != 200)
     {
         if (show.warning)
-            warning("File not found.")
+            warning("This file may not exist in the Displayr Cloud Drive or you may not have permission to access it.")
         return (FALSE)
     }
     else
@@ -92,7 +92,7 @@ QFileOpen <- function(filename, open = "r", blocking = TRUE,
         if (inherits(con, "condition")) {
             problem <- conditionMessage(con)
             if (problem == "HTTP error 404.")
-                problem <- "file not found"
+                problem <- "This file may not exist in the Displayr Cloud Drive or you may not have permission to access it."
             stopBadRequest(con, paste0("Could not open ", filename, ": ", problem))
         }
 
@@ -224,10 +224,7 @@ QLoadData <- function(filename, company.token = NA, document.token = NA,...)
     else if (res$status_code != 200)
     {
         if (!QFileExists(filename, show.warning = FALSE))
-            StopForUserError(
-                "The data file '", filename, "' does not exist in the Displayr cloud drive. ",
-                "Ensure that the data file is in the Displayr cloud drive and its name has been correctly specified."
-            )
+            StopForUserError("This file '", filename, "' may not exist in the Displayr Cloud Drive or you may not have permission to access it.")
         else
             stopBadRequest(res, msg)
     }
@@ -345,14 +342,12 @@ QSaveData <- function(object, filename, compression.file.size.threshold = NULL,
     has.errored <- inherits(res, "try-error")
 
     if (!has.errored && res$status_code == 413) # 413 comes from IIS when we violate its web.config limits
-    {
         stopBadRequest(res, "Could not write to Displayr Cloud Drive. Data to write is too large.")
-    }
-    else if (!has.errored && res$status_code == 422)
+    else if (!has.errored && res$status_code == 404)
     {
         stop("QSaveData has encountered an unknown error. ",
-             "422: The file could not properly be saved. ",
-             "The likely cause was an incorrect path preceding the filename.")
+            "404: The file could not properly be saved. ",
+            "The likely cause was an incorrect path preceding the filename, or insufficient access to the file path.")
     }
     else if (has.errored || res$status_code != 200)
     {
@@ -407,7 +402,7 @@ QDeleteFiles <- function(filenames, company.token = getCompanySecret(), document
     if (inherits(res, "try-error") || res$status_code != 200)
     {
         warning("Encountered an error deleting the following files: ", filenames.string)
-        stopBadRequest(res, paste0("Could not delete files: ", filenames.string))
+        stopBadRequest(res, paste0("Could not delete files: ", filenames.string, ". These files may not exist in the Displayr Cloud Drive or you may not have permission to access them."))
     }
     msg <- paste0("Successfully deleted files: ", filenames.string)
     message(msg)
diff --git a/tests/testthat/test-datamart.R b/tests/testthat/test-datamart.R
index 9e72e4d..b8bdaf6 100644
--- a/tests/testthat/test-datamart.R
+++ b/tests/testthat/test-datamart.R
@@ -46,15 +46,15 @@ test_that("Save/Load Data: bad cases", {
 
   # Not-existent file
   bad_name <- "anamethatdoesnotexistfortesting"
-  QFileExists(bad_name) |> expect_false() |> expect_warning("File not found")
-  QLoadData(bad_name) |> expect_error(paste0("The data file ", sQuote(bad_name, q = FALSE), " does not exist"))
+  QFileExists(bad_name) |> expect_false() |> expect_warning("may not exist in the Displayr Cloud Drive or you may not have permission")
+  QLoadData(bad_name) |> expect_error("may not exist in the Displayr Cloud Drive or you may not have permission")
 
   # Invalid filetypes
   # - note that we don't have tests for Content-Types
   QSaveData(mtcars, "mtcars.notrdsorcsv") |> expect_error("Invalid file type specified")
-    # 422 Error
+    # 404 Error
     mockedPOST <- function() {
-        list(status_code = 422)
+        list(status_code = 404)
     }
     formals(mockedPOST) <- formals(httr::POST)
     with_mocked_bindings(
@@ -63,8 +63,8 @@ test_that("Save/Load Data: bad cases", {
     ) |>
         expect_error(
             paste0("QSaveData has encountered an unknown error. ",
-                "422: The file could not properly be saved. ",
-                "The likely cause was an incorrect path preceding the filename."
+                "404: The file could not properly be saved. ",
+                "The likely cause was an incorrect path preceding the filename, or insufficient access to the file path."
                 ),
             fixed = TRUE
         )
@@ -163,7 +163,7 @@ test_that("Delete Data",
   expect_invisible(QSaveData(mtcars, "mtcars.rds"))
   expect_true(QFileExists("mtcars.rds"))
   expect_invisible(QDeleteFiles(c("mtcars.rds")))
-  expect_warning(QFileExists("mtcars.rds"), "File not found")
+  expect_warning(QFileExists("mtcars.rds"), "may not exist in the Displayr Cloud Drive or you may not have permission")
 
   expect_invisible(QSaveData(mtcars, "mtcars.csv"))
   expect_invisible(QSaveData(mtcars, "mtcars.sav"))
@@ -171,8 +171,8 @@ test_that("Delete Data",
   expect_true(QFileExists("mtcars.sav"))
 
   expect_invisible(QDeleteFiles(c("mtcars.csv", "mtcars.sav")))
-  expect_warning(QFileExists("mtcars.csv"), "File not found")
-  expect_warning(QFileExists("mtcars.sav"), "File not found")
+  expect_warning(QFileExists("mtcars.csv"), "may not exist in the Displayr Cloud Drive or you may not have permission")
+  expect_warning(QFileExists("mtcars.sav"), "may not exist in the Displayr Cloud Drive or you may not have permission")
 
   # Should still succeed even if files don't exist
   expect_invisible(QDeleteFiles(c("mtcars.csv", "mtcars.sav")))