diff --git a/Mac/Preferences/Accounts/AccountsFeedWranglerWindowController.swift b/Mac/Preferences/Accounts/AccountsFeedWranglerWindowController.swift
index 22eaf0097..5f2e2081b 100644
--- a/Mac/Preferences/Accounts/AccountsFeedWranglerWindowController.swift
+++ b/Mac/Preferences/Accounts/AccountsFeedWranglerWindowController.swift
@@ -56,6 +56,11 @@ class AccountsFeedWranglerWindowController: NSWindowController {
 			return
 		}
 		
+		guard !AccountManager.shared.duplicateServiceAccount(type: .feedWrangler, username: usernameTextField.stringValue) else {
+			self.errorMessageLabel.stringValue = NSLocalizedString("There is already a FeedWrangler account with that username created.", comment: "Duplicate Error")
+			return
+		}
+		
 		actionButton.isEnabled = false
 		progressIndicator.isHidden = false
 		progressIndicator.startAnimation(self)