--- a/ucs-school-umc-computerroom/umc/js/computerroom.js	
+++ a/ucs-school-umc-computerroom/umc/js/computerroom.js	
@@ -929,7 +929,7 @@ define([
 				}
 
 				// start finishing the exam
-				var info = this.get('roomInfo') || {};
+				var info = lang.clone(this.get('roomInfo') || {});
 				this.umcpCommand('schoolexam/exam/finish', {
 					exam: info.exam,
 					room: info.room
@@ -944,6 +944,10 @@ define([
 					deferred.resolve();
 				});
 
+				// reset room settings (prior to finishing the exam!)
+				this._settingsDialog.reset();
+				this._settingsDialog.save();
+
 				// things to do after finishing the exam
 				deferred.then(lang.hitch(this, function() {
 					return this.umcpCommand('computerroom/exam/finish', {
@@ -959,9 +963,6 @@ define([
 						delete info.examEndTime;
 						this.set('roomInfo', info);
 
-						// reset room settings
-						this._settingsDialog.reset();
-						this._settingsDialog.save();
 					}
 				}));
 			}));
--- a/ucs-school-umc-computerroom/umc/python/computerroom/__init__.py	
+++ a/ucs-school-umc-computerroom/umc/python/computerroom/__init__.py	
@@ -774,11 +778,10 @@ def settings_set(self, printMode, internetRule, shareMode, period=None, customRu
 			ucr.load()
 			if not ucr.get(varname):
 				vset[varname] = '""'
+				vunset.append(varname)
 		else:
 			# remove empty items ('""') in list
 			vset[varname] = ' '.join([x for x in vset[varname].split(' ') if x != '""'])
-		if varname in vunset:
-			del vunset[varname]
 
 		# set values
 		ucr_vars = sorted('%s=%s' % x for x in vset.items())