diff --git a/chrome/skin/default/zotero/error.png b/chrome/skin/default/zotero/error.png
index 628cf2dae3..c37bd062e6 100755
Binary files a/chrome/skin/default/zotero/error.png and b/chrome/skin/default/zotero/error.png differ
diff --git a/chrome/skin/default/zotero/error@2x.png b/chrome/skin/default/zotero/error@2x.png
index 354aa99b26..e0574d61b7 100644
Binary files a/chrome/skin/default/zotero/error@2x.png and b/chrome/skin/default/zotero/error@2x.png differ
diff --git a/chrome/skin/default/zotero/exclamation.png b/chrome/skin/default/zotero/exclamation.png
deleted file mode 100755
index c37bd062e6..0000000000
Binary files a/chrome/skin/default/zotero/exclamation.png and /dev/null differ
diff --git a/chrome/skin/default/zotero/exclamation@2x.png b/chrome/skin/default/zotero/exclamation@2x.png
deleted file mode 100644
index e0574d61b7..0000000000
Binary files a/chrome/skin/default/zotero/exclamation@2x.png and /dev/null differ
diff --git a/chrome/skin/default/zotero/overlay.css b/chrome/skin/default/zotero/overlay.css
index d3ce75b20c..6ed3b4069c 100644
--- a/chrome/skin/default/zotero/overlay.css
+++ b/chrome/skin/default/zotero/overlay.css
@@ -520,18 +520,15 @@
 }
 
 /* Sync error icon */
-#zotero-tb-sync-error, #zotero-tb-sync-error[mode=warning]
-{
+#zotero-tb-sync-error {
 	list-style-image: url(chrome://zotero/skin/error.png);
 }
 
-#zotero-tb-sync-error[mode=error]
-{
-	list-style-image: url(chrome://zotero/skin/exclamation.png);
+#zotero-tb-sync-error[state=warning] {
+	list-style-image: url(chrome://zotero/skin/warning.png);
 }
 
-#zotero-tb-sync-error[mode=upgrade]
-{
+#zotero-tb-sync-error[state=upgrade] {
 	list-style-image: url(chrome://zotero/skin/bell_error.png);
 }
 
diff --git a/chrome/skin/default/zotero/warning.png b/chrome/skin/default/zotero/warning.png
new file mode 100755
index 0000000000..628cf2dae3
Binary files /dev/null and b/chrome/skin/default/zotero/warning.png differ
diff --git a/chrome/skin/default/zotero/warning@2x.png b/chrome/skin/default/zotero/warning@2x.png
new file mode 100644
index 0000000000..354aa99b26
Binary files /dev/null and b/chrome/skin/default/zotero/warning@2x.png differ