diff --git a/src/Mod/AddonManager/AddonManager.py b/src/Mod/AddonManager/AddonManager.py
index 5ff8546e65..9bb18a9c33 100644
--- a/src/Mod/AddonManager/AddonManager.py
+++ b/src/Mod/AddonManager/AddonManager.py
@@ -270,7 +270,6 @@ class AddonsInstaller(QtGui.QDialog):
         QtGui.QDesktopServices.openUrl(QtCore.QUrl(link, QtCore.QUrl.TolerantMode))
 
     def install(self,repos=None):
-        self.buttonInstall.setEnabled(False)
         if self.tabWidget.currentIndex() == 0:
             idx = None
             if repos:
@@ -282,6 +281,9 @@ class AddonsInstaller(QtGui.QDialog):
             else:
                 idx = self.listWorkbenches.currentRow()
             if idx != None:
+                if hasattr(self,"install_worker"):
+                    if self.install_worker.isRunning():
+                        return
                 self.install_worker = InstallWorker(self.repos, idx)
                 self.install_worker.info_label.connect(self.set_information_label)
                 self.install_worker.progressbar_show.connect(self.show_progress_bar)
@@ -293,7 +295,6 @@ class AddonsInstaller(QtGui.QDialog):
             macro = self.macros[self.listMacros.currentRow()]
             if len(macro) < 5:
                 self.labelDescription.setText(translate("AddonsInstaller", "Unable to install"))
-                self.buttonInstall.setEnabled(True)
                 return
             macroname = "Macro_"+macro[0]+".FCMacro"
             macroname = macroname.replace(" ","_")
@@ -303,7 +304,6 @@ class AddonsInstaller(QtGui.QDialog):
             macrofile.close()
             self.labelDescription.setText(translate("AddonsInstaller", "Macro successfully installed. The macro is now available from the Macros dialog."))
         self.update_status()
-        self.buttonInstall.setEnabled(True)
 
     def show_progress_bar(self, state):
         if state == True: