diff --git a/web/apps/photos/src/components/Collections/AlbumCastDialog.tsx b/web/apps/photos/src/components/Collections/AlbumCastDialog.tsx
index db2009b662..322ca395bb 100644
--- a/web/apps/photos/src/components/Collections/AlbumCastDialog.tsx
+++ b/web/apps/photos/src/components/Collections/AlbumCastDialog.tsx
@@ -4,7 +4,10 @@ import { boxSeal } from "@/base/crypto";
 import log from "@/base/log";
 import type { Collection } from "@/media/collection";
 import { photosDialogZIndex } from "@/new/photos/components/utils/z-index";
-import castGateway, { revokeAllCastTokens } from "@/new/photos/services/cast";
+import castGateway, {
+    publicKeyForPairingCode,
+    revokeAllCastTokens,
+} from "@/new/photos/services/cast";
 import { loadCast } from "@/new/photos/utils/chromecast-sender";
 import SingleInputForm, {
     type SingleInputFormProps,
@@ -52,36 +55,34 @@ export const AlbumCastDialog: React.FC<AlbumCastDialogProps> = ({
         setFieldError,
     ) => {
         try {
-            await doCast(value.trim());
-            onClose();
-        } catch (e) {
-            if (e instanceof Error && e.message == "tv-not-found") {
-                setFieldError(t("tv_not_found"));
+            if (await doCast(value.trim())) {
+                onClose();
             } else {
-                setFieldError(t("generic_error_retry"));
+                setFieldError(t("tv_not_found"));
             }
+        } catch (e) {
+            log.error("Failed to cast", e);
+            setFieldError(t("generic_error_retry"));
         }
     };
 
     const doCast = async (pin: string) => {
-        // Does the TV exist? have they advertised their existence?
-        const tvPublicKeyB64 = await castGateway.getPublicKey(pin);
-        if (!tvPublicKeyB64) {
-            throw new Error("tv-not-found");
-        }
+        // Find out the public key associated with the given pairing code (if
+        // indeed a device has published one).
+        const publicKey = await publicKeyForPairingCode(pin);
+        if (!publicKey) return false;
 
         // Generate random id.
         const castToken = uuidv4();
 
-        // Ok, they exist. let's give them the good stuff.
+        // Publish the payload so that the other end can use it.
         const payload = JSON.stringify({
             castToken: castToken,
             collectionID: collection.id,
             collectionKey: collection.key,
         });
-        const encryptedPayload = await boxSeal(btoa(payload), tvPublicKeyB64);
+        const encryptedPayload = await boxSeal(btoa(payload), publicKey);
 
-        // Hey TV, we acknowlege you!
         await castGateway.publishCastPayload(
             pin,
             encryptedPayload,
diff --git a/web/packages/new/photos/services/cast.ts b/web/packages/new/photos/services/cast.ts
index e145c96c1e..3de997539e 100644
--- a/web/packages/new/photos/services/cast.ts
+++ b/web/packages/new/photos/services/cast.ts
@@ -1,9 +1,8 @@
-import { authenticatedRequestHeaders } from "@/base/http";
-import log from "@/base/log";
+import { authenticatedRequestHeaders, ensureOk } from "@/base/http";
 import { apiURL } from "@/base/origins";
-import { ApiError } from "@ente/shared/error";
 import HTTPService from "@ente/shared/network/HTTPService";
 import { getToken } from "@ente/shared/storage/localStorage/helpers";
+import { z } from "zod";
 
 /**
  * Revoke all existing outstanding cast tokens for the current user on remote.
@@ -14,28 +13,22 @@ export const revokeAllCastTokens = async () =>
         headers: await authenticatedRequestHeaders(),
     });
 
-class CastGateway {
-    public async getPublicKey(code: string): Promise<string> {
-        let resp;
-        try {
-            const token = getToken();
-            resp = await HTTPService.get(
-                await apiURL(`/cast/device-info/${code}`),
-                undefined,
-                {
-                    "X-Auth-Token": token,
-                },
-            );
-        } catch (e) {
-            if (e instanceof ApiError && e.httpStatusCode === 404) {
-                return "";
-            }
-            log.error("failed to getPublicKey", e);
-            throw e;
-        }
-        return resp.data.publicKey;
-    }
+/**
+ * Fetch the public key (represented as a base64 string) associated with the
+ * given device / pairing {@link code} from remote, or `undefined` if there is
+ * no public key associated with the given code.
+ */
+export const publicKeyForPairingCode = async (code: string) => {
+    const res = await fetch(await apiURL(`/cast/device-info/${code}`), {
+        headers: await authenticatedRequestHeaders(),
+    });
+    if (res.status == 404) return undefined;
+    ensureOk(res);
+    return z.object({ publicKey: z.string() }).parse(await res.json())
+        .publicKey;
+};
 
+class CastGateway {
     public async publishCastPayload(
         code: string,
         castPayload: string,