diff --git a/source/components/header/header.component.html b/source/components/header/header.component.html
index 763460f5b3994b09002abf902a709289cd5fcde1..868cc4ad11cb7b18c2993bda526f574370235c0b 100644
--- a/source/components/header/header.component.html
+++ b/source/components/header/header.component.html
@@ -20,20 +20,17 @@
 <div class="header-wrapper">
     <header id="navbar" role="banner" class="navbar navbar-default">
         <div class="container">
-            <div *ngIf="(loginInfo$ | async).size > 0">
+            <div *ngFor="let loginInfoRow$ of loginInfo$ | async; let i=index;">
                 <ul class="navbar-nav">
-                    <div *ngIf="(loginInfo$ | async).cu_name !== ''">
+                    <div *ngIf="loginInfoRow$.cu_name !== ''">
                         <div class="row">
                             <div class="col-md-2">
                                 <i class="fa fa-home isclickable" (click)="goHome()"></i>
                                 <span class="signout isclickable" (click)="goHome()" style="color:#CC3300;">&nbsp;&nbsp;ΑρχικΞ�</span>
-
-
                             </div>
                             <div class="col-md-2">
-                                 <span class="signout isclickable" (click)="gohelpDesk()" style="color:#CC3300;">&nbsp;&nbsp;Επικοινωνία</span>
+                                 <span *ngIf="loginInfoRow$.auth_role===studentRole" class="signout isclickable" (click)="gohelpDesk()" style="color:#CC3300;">Επικοινωνία</span>
                             </div>
-                            
 
                             <div class="col-md-4">&nbsp;</div>
                             <div class="col-md-4" style="text-align: right">
diff --git a/source/components/header/header.component.ts b/source/components/header/header.component.ts
index 8b3ab5b79b604c3e16b1e4a56c9ea2a5820347ef..8a368a042e621fbcf6eb711b5dc00a755d162bcf 100644
--- a/source/components/header/header.component.ts
+++ b/source/components/header/header.component.ts
@@ -23,6 +23,7 @@ import { StudentDataFieldsActions } from "../../actions/studentdatafields.action
 })
 export default class HeaderComponent implements OnInit, OnDestroy {
     private authToken: string;
+    private studentRole = STUDENT_ROLE;
     private authRole: string;
     private cuName: string;
     private loginInfo$: BehaviorSubject<ILoginInfo>;
@@ -141,7 +142,7 @@ export default class HeaderComponent implements OnInit, OnDestroy {
 
     gohelpDesk()
     {
-       this.router.navigate(['/help-desk']); 
+       this.router.navigate(['/help-desk']);
     }
 
     public showModal(): void {
diff --git a/source/components/main/main.component.html b/source/components/main/main.component.html
index 4a33bd1e318492bece2c48f15ad5f67499d4281c..05416ed3da7687a132465cd54e00509005055147 100644
--- a/source/components/main/main.component.html
+++ b/source/components/main/main.component.html
@@ -25,10 +25,9 @@
           <div style="margin-top:15px; margin-bottom: 10px;" class="left-choices">
             <div class="row">
             <div class="col-md-12">
-                <button type="button" class="btn-primary btn-lg pull-left isclickable" style="width: 10em;" >
-                <a style="font-size: 0.9em; font-family: arial, sans-serif!important; font-weight: bold; color: #ffffff;" href="../pdfs/files/odigies.pdf" target="_blank">ΞŸΞ΄Ξ·Ξ³Ξ―Ξ΅Ο‚ χρΞ�σης</a>
-
-                </button>
+                <a href="/pdfs/files/odigies.pdf" target="_blank" class="btn btn-primary btn-lg pull-left isclickable active" style="width: 10em; " role="button" aria-pressed="true">
+                    <span style="font-size: 0.9em; font-family: arial, sans-serif!important; font-weight: bold; color: #ffffff;">ΞŸΞ΄Ξ·Ξ³Ξ―Ξ΅Ο‚ χρΞ�σης</span>
+                </a>
             </div>
             </div>
           </div>