diff --git a/quartz-manager-frontend/src/app/components/simple-trigger-config/simple-trigger-config.component.html b/quartz-manager-frontend/src/app/components/simple-trigger-config/simple-trigger-config.component.html
index fca9367..c4321fc 100644
--- a/quartz-manager-frontend/src/app/components/simple-trigger-config/simple-trigger-config.component.html
+++ b/quartz-manager-frontend/src/app/components/simple-trigger-config/simple-trigger-config.component.html
@@ -29,7 +29,7 @@
           >
             <mat-label>Job Class *</mat-label>
             <mat-select id="jobClass" name="jobClass" formControlName="jobClass" [disabled]="!enabledTriggerForm">
-              <mat-option *ngFor="let job of jobs" [value]="job">
+              <mat-option *ngFor="let job of jobs" [value]="job" style="font-size: 0.8em">
                 {{job}}
               </mat-option>
             </mat-select>
@@ -46,7 +46,7 @@
           >
             <mat-label>Misfire Instruction *</mat-label>
             <mat-select id="misfireInstruction" name="misfireInstruction" formControlName="misfireInstruction"
-                        [disabled]="!enabledTriggerForm">
+                        [disabled]="!enabledTriggerForm" style="font-size: 0.8em">
               <mat-option value="MISFIRE_INSTRUCTION_FIRE_NOW">FIRE NOW</mat-option>
               <mat-option value="MISFIRE_INSTRUCTION_RESCHEDULE_NOW_WITH_EXISTING_REPEAT_COUNT">RESCHEDULE NOW WITH
                 EXISTING REPEAT COUNT
@@ -110,6 +110,9 @@
                 <!--                                       [enableMeridian]="enableMeridian" [disableMinute]="disableMinute" [hideTime]="hideTime">-->
               </ngx-mat-datetime-picker>
             </mat-form-field>
+            <mat-error *ngIf="simpleTriggerReactiveForm.controls.triggerPeriod.errors?.invalidTriggerPeriod" style="font-size: small">
+              the end date cannot be  <strong>before</strong> the start date
+            </mat-error>
           </div>
         </div>
 
@@ -125,9 +128,14 @@
                      matInput placeholder="Repeat Interval [in mills]" type="number"
                      formControlName="repeatInterval" name="repeatInterval"
               >
+              <mat-error *ngIf="simpleTriggerReactiveForm.controls.triggerRecurrence.errors?.invalidTriggerRecurrence">
+                repeatCount and repeatInterval must be <strong>both</strong> set or unset
+              </mat-error>
             </mat-form-field>
+<!--            <mat-error *ngIf="simpleTriggerReactiveForm.controls.triggerRecurrence.errors?.invalidTriggerRecurrence" style="font-size: small">-->
+<!--              repeatCount and repeatInterval must be <strong>both</strong> set or unset-->
+<!--            </mat-error>-->
           </div>
-
           <div>
             <mat-form-field
               [appearance]="enabledTriggerForm ? 'standard': 'none'"
@@ -139,10 +147,16 @@
                      matInput placeholder="Repeat Count (-1 REPEAT INDEFINITELY)" type="number"
                      formControlName="repeatCount" name="repeatCount"
               >
+              <mat-error *ngIf="simpleTriggerReactiveForm.controls.triggerRecurrence.errors?.invalidTriggerRecurrence">
+                repeatCount and repeatInterval must be <strong>both</strong> set or unset
+              </mat-error>
             </mat-form-field>
+
           </div>
         </div>
 
+        <br/>
+
         <button mat-raised-button
                 type="button"
                 *ngIf="enabledTriggerForm"
diff --git a/quartz-manager-frontend/src/app/components/simple-trigger-config/simple-trigger-config.component.spec.ts b/quartz-manager-frontend/src/app/components/simple-trigger-config/simple-trigger-config.component.spec.ts
index d958c67..4e70ca5 100644
--- a/quartz-manager-frontend/src/app/components/simple-trigger-config/simple-trigger-config.component.spec.ts
+++ b/quartz-manager-frontend/src/app/components/simple-trigger-config/simple-trigger-config.component.spec.ts
@@ -107,6 +107,12 @@ describe('SimpleTriggerConfig', () => {
     expect(submitButton.nativeElement.getAttribute('disabled')).toEqual('');
     setMatSelectValueByIndex(componentDe, '#jobClass', 0);
     expect(submitButton.nativeElement.getAttribute('disabled')).toEqual(null);
+
+    setInputValue(componentDe, '#repeatCount', '1000');
+    expect(submitButton.nativeElement.getAttribute('disabled')).toEqual('');
+
+    setInputValue(componentDe, '#repeatInterval', '2000');
+    expect(submitButton.nativeElement.getAttribute('disabled')).toEqual(null);
   }
 
   it('should enabled the submit only when the form is valid', () => {
diff --git a/quartz-manager-frontend/src/app/components/simple-trigger-config/simple-trigger-config.component.ts b/quartz-manager-frontend/src/app/components/simple-trigger-config/simple-trigger-config.component.ts
index 57390e5..9fdc74f 100644
--- a/quartz-manager-frontend/src/app/components/simple-trigger-config/simple-trigger-config.component.ts
+++ b/quartz-manager-frontend/src/app/components/simple-trigger-config/simple-trigger-config.component.ts
@@ -8,7 +8,7 @@ import * as moment from 'moment';
 import {TriggerKey} from '../../model/triggerKey.model';
 import JobService from '../../services/job.service';
 import {MisfireInstruction, MisfireInstructionCaption} from '../../model/misfire-instruction.model';
-import {FormBuilder, FormControl, FormGroup, Validators} from '@angular/forms';
+import {AbstractControl, FormBuilder, FormControl, FormGroup, ValidationErrors, ValidatorFn, Validators} from '@angular/forms';
 
 @Component({
   selector: 'qrzmng-simple-trigger-config',
@@ -25,17 +25,14 @@ export class SimpleTriggerConfigComponent implements OnInit {
     triggerPeriod: this.formBuilder.group({
       startDate: [this.trigger?.startTime && moment(this.trigger?.startTime)],
       endDate: [this.trigger?.endTime && moment(this.trigger?.endTime)]
-    }),
+    }, {validators: this._triggerPeriodValidator}),
     triggerRecurrence: this.formBuilder.group({
       repeatCount: [this.trigger?.repeatCount],
       repeatInterval: [this.trigger?.repeatInterval]
-    }),
+    }, {validators: this._triggerRepetitionValidator}),
     misfireInstruction: [MisfireInstruction[this.trigger?.misfireInstruction], Validators.required]
   });
 
-  // simpleTriggerForm: SimpleTriggerForm = new SimpleTriggerForm();
-  // formBackup: SimpleTriggerForm = new SimpleTriggerForm();
-
   scheduler: Scheduler;
 
   triggerLoading = true;
@@ -88,8 +85,6 @@ export class SimpleTriggerConfigComponent implements OnInit {
       .subscribe((retTrigger: SimpleTrigger) => {
         this.trigger = retTrigger;
         this.simpleTriggerReactiveForm.setValue(this._fromTriggerToReactiveForm(retTrigger))
-        // this.formBackup = this.simpleTriggerForm;
-        // this.simpleTriggerForm = this._fromTriggerToForm(retTrigger);
         this.triggerLoading = false;
         this.triggerInProgress = this.trigger.mayFireAgain;
       })
@@ -129,6 +124,30 @@ export class SimpleTriggerConfigComponent implements OnInit {
 
   }
 
+  private _triggerPeriodValidator(control: AbstractControl): ValidationErrors | null {
+    const startDate = control.get('startDate');
+    const endDate = control.get('endDate');
+    if (startDate.value && endDate.value) {
+      return endDate.value.isBefore(startDate.value) ?
+        <ValidationErrors>{invalidTriggerPeriod: true} : null;
+    }
+    return null;
+  }
+
+  private _triggerRepetitionValidator(control: AbstractControl): ValidationErrors | null {
+    const repeatInterval = control.get('repeatInterval');
+    const repeatCount = control.get('repeatCount');
+    if ((repeatCount.value && repeatInterval.value) || (!repeatCount.value && !repeatInterval.value)) {
+      repeatInterval.setErrors(null);
+      repeatCount.setErrors(null);
+      return null;
+    }
+    const errors = <ValidationErrors>{invalidTriggerRecurrence: true};
+    repeatInterval.setErrors(errors);
+    repeatCount.setErrors(errors);
+    return errors;
+  }
+
   private _fromTriggerToReactiveForm = (simpleTrigger: SimpleTrigger): SimpleTriggerReactiveForm => {
     const simpleTriggerReactiveForm = new SimpleTriggerReactiveForm();
     simpleTriggerReactiveForm.triggerName = simpleTrigger.triggerKeyDTO.name;
@@ -137,22 +156,11 @@ export class SimpleTriggerConfigComponent implements OnInit {
     simpleTriggerReactiveForm.triggerRecurrence.repeatInterval = simpleTrigger.repeatInterval || null;
     simpleTriggerReactiveForm.triggerPeriod.startDate = (simpleTrigger.startTime && moment(simpleTrigger.startTime)) || null;
     simpleTriggerReactiveForm.triggerPeriod.endDate = (simpleTrigger.endTime && moment(simpleTrigger.endTime)) || null;
-    simpleTriggerReactiveForm.misfireInstruction = (simpleTrigger.misfireInstruction && MisfireInstruction[simpleTrigger.misfireInstruction]) || null;
+    simpleTriggerReactiveForm.misfireInstruction = (simpleTrigger.misfireInstruction
+      && MisfireInstruction[simpleTrigger.misfireInstruction]) || null;
     return simpleTriggerReactiveForm;
   };
 
-  private _fromTriggerToForm = (simpleTrigger: SimpleTrigger): SimpleTriggerForm => {
-    const command = new SimpleTriggerForm();
-    command.triggerName = simpleTrigger.triggerKeyDTO.name;
-    command.jobClass = simpleTrigger.jobDetailDTO.jobClassName;
-    command.repeatCount = simpleTrigger.repeatCount;
-    command.repeatInterval = simpleTrigger.repeatInterval;
-    command.startDate = moment(simpleTrigger.startTime);
-    command.endDate = moment(simpleTrigger.endTime);
-    command.misfireInstruction = MisfireInstruction[simpleTrigger.misfireInstruction];
-    return command;
-  }
-
   private _fromReactiveFormToCommand = (): SimpleTriggerCommand => {
     const reactiveFormValue = this.simpleTriggerReactiveForm.value;
     const simpleTriggerCommand = new SimpleTriggerCommand();
@@ -167,7 +175,8 @@ export class SimpleTriggerConfigComponent implements OnInit {
   }
 
   getMisfireInstructionCaption(): string {
-    const misfireInstructionKey = this.simpleTriggerReactiveForm.controls.misfireInstruction.value as unknown as keyof typeof MisfireInstruction;
+    const misfireInstructionKey = this.simpleTriggerReactiveForm.controls
+      .misfireInstruction.value as unknown as keyof typeof MisfireInstruction;
     return MisfireInstructionCaption.get(MisfireInstruction[misfireInstructionKey]);
   }
 }