diff --git a/gnucash/gnome-utils/gnc-file.c b/gnucash/gnome-utils/gnc-file.c
index 2eefc34a69..0f8e0e4bd3 100644
--- a/gnucash/gnome-utils/gnc-file.c
+++ b/gnucash/gnome-utils/gnc-file.c
@@ -45,6 +45,7 @@
 #include "gnc-window.h"
 #include "gnc-plugin-file-history.h"
 #include "qof.h"
+#include "Scrub.h"
 #include "TransLog.h"
 #include "gnc-session.h"
 #include "gnc-state.h"
@@ -1023,6 +1024,12 @@ RESTART:
         gnc_warning_dialog(parent, "%s", message);
         g_free ( message );
     }
+
+    // Fix account color slots being set to 'Not Set', should run once on a book
+    qof_event_suspend();
+    xaccAccountScrubColorNotSet (gnc_get_current_book());
+    qof_event_resume();
+
     return TRUE;
 }
 
diff --git a/libgnucash/engine/Scrub.c b/libgnucash/engine/Scrub.c
index d6ff1075ff..38aa240569 100644
--- a/libgnucash/engine/Scrub.c
+++ b/libgnucash/engine/Scrub.c
@@ -1114,15 +1114,15 @@ xaccTransScrubCurrency (Transaction *trans)
                 }
                 else
                 {
-		    gnc_commodity *currency = xaccAccountGetCommodity(split->acc);
+                    gnc_commodity *currency = xaccAccountGetCommodity(split->acc);
                     PWARN ("setting to split=\"%s\" account=\"%s\" commodity=\"%s\"",
                            split->memo, xaccAccountGetName(split->acc),
                            gnc_commodity_get_mnemonic(currency));
 
-		    xaccTransBeginEdit (trans);
-		    xaccTransSetCurrency (trans, currency);
-		    xaccTransCommitEdit (trans);
-		    return;
+                    xaccTransBeginEdit (trans);
+                    xaccTransSetCurrency (trans, currency);
+                    xaccTransCommitEdit (trans);
+                    return;
                 }
             }
         }
@@ -1354,6 +1354,42 @@ xaccAccountScrubKvp (Account *account)
 
 /* ================================================================ */
 
+void
+xaccAccountScrubColorNotSet (QofBook *book)
+{
+    GValue value_s = G_VALUE_INIT;
+
+    // get the run-once value
+    qof_instance_get_kvp (QOF_INSTANCE (book), &value_s, 1, "remove-color-not-set-slots");
+
+    if (G_VALUE_HOLDS_STRING (&value_s) && (strcmp(g_value_get_string (&value_s), "true") == 0))
+        return;
+    else
+    {
+        GValue value_b = G_VALUE_INIT;
+        Account *root = gnc_book_get_root_account (book);
+        GList *accts = gnc_account_get_descendants_sorted (root);
+        GList *ptr;
+
+        for (ptr = accts; ptr; ptr = g_list_next (ptr))
+        {
+            const gchar *color = xaccAccountGetColor (ptr->data);
+
+            if (g_strcmp0 (color, "Not Set") == 0)
+                xaccAccountSetColor (ptr->data, "");
+        }
+        g_list_free (accts);
+
+        g_value_init (&value_b, G_TYPE_BOOLEAN);
+        g_value_set_boolean (&value_b, TRUE);
+
+        // set the run-once value
+        qof_instance_set_kvp (QOF_INSTANCE (book),  &value_b, 1, "remove-color-not-set-slots");
+    }
+}
+
+/* ================================================================ */
+
 Account *
 xaccScrubUtilityGetOrMakeAccount (Account *root, gnc_commodity * currency,
                                   const char *accname, GNCAccountType acctype,
diff --git a/libgnucash/engine/Scrub.h b/libgnucash/engine/Scrub.h
index d57fadf1d7..9536f8c34b 100644
--- a/libgnucash/engine/Scrub.h
+++ b/libgnucash/engine/Scrub.h
@@ -145,6 +145,11 @@ void xaccAccountTreeScrubQuoteSources (Account *root, gnc_commodity_table *table
 /** Removes empty "notes", "placeholder", and "hbci" KVP slots from Accounts. */
 void xaccAccountScrubKvp (Account *account);
 
+/** Remove color slots that have a "Not Set" value, since 2.4.0, fixed in 3.4
+ *  This should only be run once on a book
+ */
+void xaccAccountScrubColorNotSet (QofBook *book);
+
 /** Changes Transaction date_posted timestamps from 00:00 local to 11:00 UTC.
  * 11:00 UTC is the same day local time in almost all timezones, the exceptions
  * being the -12, +13, and +14 timezones along the International Date Line. If