diff --git a/app/static/js/App.js b/app/static/js/App.js
index e20b30f2..ea8d20f7 100644
--- a/app/static/js/App.js
+++ b/app/static/js/App.js
@@ -16,10 +16,24 @@ class App {
     this.data.promises.getUser[userId] = new Promise((resolve, reject) => {
       fetch(`/users/${userId}?backrefs=true&relationships=true`, {headers: {Accept: 'application/json'}})
         .then(
-          (response) => {return response.json();},
           (response) => {
-            if (response.status === 403) {this.flash('Forbidden', 'error');}
-            if (response.status === 404) {this.flash('Not Found', 'error');}
+            switch (response.status) {
+              case 403: {
+                this.flash('Forbidden', 'error');
+                break;
+              }
+              case 404: {
+                this.flash('Not Found', 'error');
+                break;
+              }
+              default: {
+                response.json();
+                break;
+              }
+            }
+          },
+          (response) => {
+            this.flash('Something went wrong', 'error');
             reject(response);
           }
         )
diff --git a/app/static/js/RessourceLists/SpacyNLPPipelineModelList.js b/app/static/js/RessourceLists/SpacyNLPPipelineModelList.js
index 057e7c4c..1d7ddce4 100644
--- a/app/static/js/RessourceLists/SpacyNLPPipelineModelList.js
+++ b/app/static/js/RessourceLists/SpacyNLPPipelineModelList.js
@@ -31,7 +31,7 @@ class SpaCyNLPPipelineModelList extends RessourceList {
         <td><b><span class="title"></span> <span class="version"></span></b><br><i><span class="description"></span></i></td>
         <td><a class="publisher-url"><span class="publisher"></span></a> (<span class="publishing-year"></span>)<br><a class="publishing-url"><span class="publishing-url-2"></span></a></td>
         <td>
-          <div class="switch action-switch center-align" data-action="share-request">
+          <div class="switch action-switch center-align" data-action="share-request" data-user-role=>
             <span class="share"></span>
             <label>
               <input type="checkbox" class="shared">
@@ -86,6 +86,11 @@ class SpaCyNLPPipelineModelList extends RessourceList {
 
   init (user) {
     this._init(user.spacy_nlp_pipeline_models);
+    for (let switchElement of this.listjs.list.querySelectorAll('.shared')) {
+      if (user.role.name !== 'Administrator' || user.role.name !== 'Contributor') {
+        switchElement.setAttribute('disabled', '');
+      }
+    }
   }
 
   _init(ressources) {
diff --git a/app/static/js/Utils.js b/app/static/js/Utils.js
index 31c89087..010ed0d2 100644
--- a/app/static/js/Utils.js
+++ b/app/static/js/Utils.js
@@ -12,13 +12,27 @@ class Utils {
       fetch(`/corpora/${corpus.id}/build`, {method: 'POST', headers: {Accept: 'application/json'}})
         .then(
           (response) => {
-            app.flash(`Corpus "${corpus.title}" marked for building`, 'corpus');
-            resolve(response);
+            switch(response.status) {
+              case 403:
+                app.flash('Forbidden', 'error');
+                reject(response);
+                break;
+              case 404:
+                app.flash('Not Found', 'error');
+                reject(response);
+                break;
+              case 409:
+                app.flash('Conflict', 'error');
+                reject(response);
+                break;
+              default:
+                app.flash(`Corpus "${corpus.title}" marked for building`, 'corpus');
+                resolve(response);
+                break;
+            }
           },
           (response) => {
-            if (response.status === 403) {app.flash('Forbidden', 'error');}
-            if (response.status === 404) {app.flash('Not Found', 'error');}
-            if (response.status === 409) {app.flash('Conflict', 'error');}
+            app.flash('Something went wrong', 'error');
             reject(response);
           }
         );
@@ -61,12 +75,23 @@ class Utils {
         fetch(`/corpora/${corpus.id}`, {method: 'DELETE', headers: {Accept: 'application/json'}})
           .then(
             (response) => {
-              app.flash(`Corpus "${corpusTitle}" marked for deletion`, 'corpus');
-              resolve(response);
+              switch(response.status) {
+                case 403:
+                  app.flash('Forbidden', 'error');
+                  reject(response);
+                  break;
+                case 404:
+                  app.flash('Not Found', 'error');
+                  reject(response);
+                  break;
+                default:
+                  app.flash(`Corpus "${corpus.title}" marked for deletion`, 'corpus');
+                  resolve(response);
+                  break;
+              }
             },
             (response) => {
-              if (response.status === 403) {app.flash('Forbidden', 'error');}
-              if (response.status === 404) {app.flash('Not Found', 'error');}
+              app.flash('Something went wrong', 'error');
               reject(response);
             }
           );
@@ -112,12 +137,23 @@ class Utils {
         fetch(`/corpora/${corpusId}/files/${corpusFileId}`, {method: 'DELETE', headers: {Accept: 'application/json'}})
           .then(
             (response) => {
-              app.flash(`Corpus file "${corpusFileTitle}" marked for deletion`, 'corpus');
-              resolve(response);
+              switch(response.status) {
+                case 403:
+                  app.flash('Forbidden', 'error');
+                  reject(response);
+                  break;
+                case 404:
+                  app.flash('Not Found', 'error');
+                  reject(response);
+                  break;
+                default:
+                  app.flash(`Corpus file "${corpusFileTitle}" marked for deletion`, 'corpus');
+                  resolve(response);
+                  break;
+              }
             },
             (response) => {
-              if (response.status === 403) {app.flash('Forbidden', 'error');}
-              if (response.status === 404) {app.flash('Not Found', 'error');}
+              app.flash('Something went wrong', 'error');
               reject(response);
             }
           );
@@ -160,12 +196,23 @@ class Utils {
         fetch(`/contributions/spacy-nlp-pipeline-models/${spaCyNLPPipelineModelId}`, {method: 'DELETE'})
           .then(
             (response) => {
-              app.flash(`SpaCy NLP Pipeline Model "${spaCyNLPPipelineModelTitle}" marked for deletion`);
-              resolve(response);
+              switch(response.status) {
+                case 403:
+                  app.flash('Forbidden', 'error');
+                  reject(response);
+                  break;
+                case 404:
+                  app.flash('Not Found', 'error');
+                  reject(response);
+                  break;
+                default:
+                  app.flash(`SpaCy NLP Pipeline Model "${spaCyNLPPipelineModelTitle}" marked for deletion`);
+                  resolve(response);
+                  break;
+              }
             },
             (response) => {
-              if (response.status === 403) {app.flash('Forbidden', 'error');}
-              if (response.status === 404) {app.flash('Not Found', 'error');}
+              app.flash('Something went wrong', 'error');
               reject(response);
             }
           );
@@ -208,12 +255,24 @@ class Utils {
         fetch(`/contributions/tesseract-ocr-pipeline-models/${tesseractOCRPipelineModelId}`, {method: 'DELETE'})
           .then(
             (response) => {
-              app.flash(`Tesseract OCR Pipeline Model "${tesseractOCRPipelineModelTitle}" marked for deletion`);
-              resolve(response);
+              switch(response.status) {
+                case 403:
+                  app.flash('Forbidden', 'error');
+                  reject(response);
+                  break;
+                case 404:
+                  app.flash('Not Found', 'error');
+                  reject(response);
+                  break;
+                default:
+                  app.flash(`Tesseract OCR Pipeline Model "${tesseractOCRPipelineModelTitle}" marked for deletion`);
+                  resolve(response);
+                  break;
+              }
+              
             },
             (response) => {
-              if (response.status === 403) {app.flash('Forbidden', 'error');}
-              if (response.status === 404) {app.flash('Not Found', 'error');}
+              app.flash('Something went wrong', 'error');
               reject(response);
             }
           );
@@ -258,12 +317,23 @@ class Utils {
         fetch(`/jobs/${job.id}`, {method: 'DELETE', headers: {Accept: 'application/json'}})
           .then(
             (response) => {
-              app.flash(`Job "${jobTitle}" marked for deletion`, 'job');
-              resolve(response);
+              switch(response.status) {
+                case 403:
+                  app.flash('Forbidden', 'error');
+                  reject(response);
+                  break;
+                case 404:
+                  app.flash('Not Found', 'error');
+                  reject(response);
+                  break;
+                default:
+                  app.flash(`Job "${jobTitle}" marked for deletion`, 'job');
+                  resolve(response);
+                  break;
+              }
             },
             (response) => {
-              if (response.status === 403) {app.flash('Forbidden', 'error');}
-              if (response.status === 404) {app.flash('Not Found', 'error');}
+              app.flash('Something went wrong', 'error');
               reject(response);
             }
           );
@@ -279,12 +349,23 @@ class Utils {
       fetch(`/jobs/${job.id}/log`, {method: 'GET', headers: {Accept: 'application/json, text/plain'}})
         .then(
           (response) => {
-            resolve(response);
-            return response.text();
+            switch(response.status) {
+              case 403:
+                app.flash('Forbidden', 'error');
+                reject(response);
+                break;
+              case 404:
+                app.flash('Not Found', 'error');
+                reject(response);
+                break;
+              default:
+                resolve(response);
+                response.text();
+                break;
+            }
           },
           (response) => {
-            if (response.status === 403) {app.flash('Forbidden', 'error');}
-            if (response.status === 404) {app.flash('Not Found', 'error');}
+            app.flash('Something went wrong', 'error');
             reject(response);
           }
         )
@@ -355,13 +436,26 @@ class Utils {
         fetch(`/jobs/${job.id}/restart`, {method: 'POST', headers: {Accept: 'application/json'}})
           .then(
             (response) => {
-              app.flash(`Job "${jobTitle}" restarted.`, 'job');
-              resolve(response);
+              switch(response.status) {
+                case 403:
+                  app.flash('Forbidden', 'error');
+                  reject(response);
+                  break;
+                case 404:
+                  app.flash('Not Found', 'error');
+                  reject(response);
+                  break;
+                case 409:
+                  app.flash('Conflict', 'error');
+                  reject(response);
+                default:
+                  app.flash(`Job "${jobTitle}" restarted.`, 'job');
+                  resolve(response);
+                  break;
+              }
             },
             (response) => {
-              if (response.status === 403) {app.flash('Forbidden', 'error');}
-              if (response.status === 404) {app.flash('Not Found', 'error');}
-              if (response.status === 409) {app.flash('Conflict', 'error');}
+              app.flash('Something went wrong', 'error');
               reject(response);
             }
           );
@@ -406,12 +500,24 @@ class Utils {
         fetch(`/users/${user.id}`, {method: 'DELETE', headers: {Accept: 'application/json'}})
           .then(
             (response) => {
-              app.flash(`User "${userName}" marked for deletion`);
-              resolve(response);
+              switch(response.status) {
+                case 403:
+                  app.flash('Forbidden', 'error');
+                  reject(response);
+                  break;
+                case 404:
+                  app.flash('Not Found', 'error');
+                  reject(response);
+                  break;
+                default:
+                  app.flash(`User "${userName}" marked for deletion`);
+                  resolve(response);
+                  break;
+              }
+              
             },
             (response) => {
-              if (response.status === 403) {app.flash('Forbidden', 'error');}
-              if (response.status === 404) {app.flash('Not Found', 'error');}
+              app.flash('Something went wrong', 'error');
               reject(response);
             }
           );
@@ -432,11 +538,19 @@ class Utils {
       fetch(`/contributions/tesseract-ocr-pipeline-models/${tesseractOCRPipelineModel.id}/toggle-public-status`, {method: 'POST', headers: {Accept: 'application/json'}})
       .then(
         (response) => {
-          app.flash(msg, 'corpus');
-          resolve(response);
+          switch(response.status) {
+            case 403:
+              app.flash('Forbidden', 'error');
+              reject(response);
+              break;
+            default:
+              app.flash(msg, 'corpus');
+              resolve(response);
+              break;
+          }
         },
         (response) => {
-          if (response.status === 403) {app.flash('Forbidden', 'error');}
+          app.flash('Something went wrong', 'error');
           reject(response);
         }
       );
@@ -455,11 +569,19 @@ class Utils {
       fetch(`/contributions/spacy-nlp-pipeline-models/${spaCyNLPPipelineModel.id}/toggle-public-status`, {method: 'POST', headers: {Accept: 'application/json'}})
       .then(
         (response) => {
-          app.flash(msg, 'corpus');
-          resolve(response);
+          switch(response.status) {
+            case 403:
+              app.flash('Forbidden', 'error');
+              reject(response);
+              break;
+            default:
+              app.flash(msg, 'corpus');
+              resolve(response);
+              break;
+          }
         },
         (response) => {
-          if (response.status === 403) {app.flash('Forbidden', 'error');}
+          app.flash('Something went wrong', 'error');
           reject(response);
         }
       );