diff --git a/projects/aas-lib/src/lib/aas-tree/aas-tree-api.service.ts b/projects/aas-lib/src/lib/aas-tree/aas-tree-api.service.ts
index 08c5e2c..35d7940 100644
--- a/projects/aas-lib/src/lib/aas-tree/aas-tree-api.service.ts
+++ b/projects/aas-lib/src/lib/aas-tree/aas-tree-api.service.ts
@@ -52,4 +52,24 @@ export class AASTreeApiService {
                 });
         });
     }
+
+    /**
+     * Reads the value of an data element like `File` or `Blob`.
+     * @param endpoint The endpoint name
+     * @param id The AAS identifier.
+     * @param smId The submodel identifier.
+     * @param path The idShort path of the submodel element.
+     * @returns The Base64 encoded value.
+     */
+    public getValueAsync(endpoint: string, id: string, smId: string, path: string): Promise<string> {
+        return new Promise<string>((result, reject) => {
+            let data: string;
+            const url = `/api/v1/containers/${encodeBase64Url(endpoint)}/documents/${encodeBase64Url(id)}/submodels/${encodeBase64Url(smId)}/submodel-elements/${path}/value`;
+            this.http.get<{ value: string }>(url).subscribe({
+                next: value => (data = value.value),
+                complete: () => result(data),
+                error: error => reject(error),
+            });
+        });
+    }
 }
diff --git a/projects/aas-lib/src/lib/aas-tree/aas-tree.component.ts b/projects/aas-lib/src/lib/aas-tree/aas-tree.component.ts
index 1b08e1e..068752e 100644
--- a/projects/aas-lib/src/lib/aas-tree/aas-tree.component.ts
+++ b/projects/aas-lib/src/lib/aas-tree/aas-tree.component.ts
@@ -276,32 +276,31 @@ export class AASTreeComponent implements OnInit, OnDestroy {
             name += extension;
         }
 
-        if (blob.value) {
-            if (blob.contentType.startsWith('image/')) {
-                await this.showImageAsync(name, `data:${blob.contentType};base64,${blob.value}`);
-            } else if (blob.contentType.startsWith('video/')) {
-                await this.showVideoAsync(name, `data:${blob.contentType};base64,${blob.value}`);
-            }
-        } else {
-            const endpoint = encodeBase64Url(document.endpoint);
-            const id = encodeBase64Url(document.id);
-            const smId = encodeBase64Url(blob.parent.keys[0].value);
-            const path = getIdShortPath(blob);
-            const url = `/api/v1/containers/${endpoint}/documents/${id}/submodels/${smId}/submodel-elements/${path}/value`;
-            if (blob.contentType.startsWith('image/')) {
-                await this.showImageAsync(name, url);
-            } else if (blob.contentType.startsWith('video/')) {
-                await this.showVideoAsync(name, url);
-            } else if (blob.contentType.endsWith('/pdf')) {
-                this.window.open(url);
-            } else if (blob) {
-                await this.downloadFileAsync(name, url);
+        if (!blob.value) {
+            try {
+                blob.value = await this.api.getValueAsync(
+                    document.endpoint,
+                    document.id,
+                    blob.parent.keys[0].value,
+                    getIdShortPath(blob),
+                );
+            } catch (error) {
+                this.notify.error(error);
+                return;
             }
         }
+
+        if (blob.contentType.startsWith('image/')) {
+            await this.showImageAsync(name, `data:${blob.contentType};base64,${blob.value}`);
+        } else if (blob.contentType.startsWith('video/')) {
+            await this.showVideoAsync(name, `data:${blob.contentType};base64,${blob.value}`);
+        }
     }
 
     public async openOperation(operation: aas.Operation | undefined): Promise<void> {
-        if (!operation || this.state() === 'online') return;
+        if (!operation || this.state() === 'online') {
+            return;
+        }
 
         try {
             if (operation) {
diff --git a/projects/aas-server/src/app/aas-provider/aas-provider.ts b/projects/aas-server/src/app/aas-provider/aas-provider.ts
index 3166799..2ecad17 100644
--- a/projects/aas-server/src/app/aas-provider/aas-provider.ts
+++ b/projects/aas-server/src/app/aas-provider/aas-provider.ts
@@ -185,7 +185,7 @@ export class AASProvider {
             } else if (dataElement.modelType === 'Blob') {
                 const value = await resource.getBlobValueAsync(document.content, smId, path);
                 const readable = new Readable();
-                readable.push(value);
+                readable.push(JSON.stringify({ value }));
                 readable.push(null);
                 stream = readable;
             } else {