diff --git a/chrome/content/zotero/overlay.js b/chrome/content/zotero/overlay.js
index 43241c667..174e6ef80 100644
--- a/chrome/content/zotero/overlay.js
+++ b/chrome/content/zotero/overlay.js
@@ -103,6 +103,13 @@ var ZoteroOverlay = new function()
 			if(newMode == "connector") {
 				// save current state
 				_stateBeforeReload = !zoteroPane.hidden && !zoteroPane.collapsed;
+				
+				// Don't display startup error when Standalone opens
+				if (Zotero.startupError) {
+					Zotero.debug(startupError, 1);
+					return;
+				}
+				
 				// ensure pane is closed
 				if(!zoteroPane.collapsed) ZoteroOverlay.toggleDisplay(false, true);
 			}
diff --git a/chrome/content/zotero/xpcom/zotero.js b/chrome/content/zotero/xpcom/zotero.js
index ecc1fd6eb..b00e86559 100644
--- a/chrome/content/zotero/xpcom/zotero.js
+++ b/chrome/content/zotero/xpcom/zotero.js
@@ -611,6 +611,8 @@ Components.utils.import("resource://gre/modules/Services.jsm");
 			}
 			catch (e) {
 				if (e instanceof Zotero.DB.IncompatibleVersionException) {
+					Zotero.DB.closeDatabase(true).then(() => Zotero.debug("Database closed"));
+					
 					let kbURL = "https://www.zotero.org/support/kb/newer_db_version";
 					let msg = (e.dbClientVersion
 						? Zotero.getString('startupError.incompatibleDBVersion',