diff --git a/src/utils/wrapFunctionsInTelemetry.ts b/src/utils/wrapFunctionsInTelemetry.ts
index ac31c2e4..1000e06e 100644
--- a/src/utils/wrapFunctionsInTelemetry.ts
+++ b/src/utils/wrapFunctionsInTelemetry.ts
@@ -16,7 +16,7 @@ function stringifyError(e: unknown): string {
 }
 
 function handleError(e: unknown, functionName: string): never {
-    ext.outputChannel.appendLog(`Internal error: '${functionName}' threw an exception\n\t${stringifyError(e)}`);
+    ext.outputChannel?.appendLog(`Internal error: '${functionName}' threw an exception\n\t${stringifyError(e)}`);
     if (e instanceof Error) {
         e.message = functionName === 'branchDataProvider.getResourceItem' ?
             // shortened message for anything displayed on the tree
diff --git a/test/nightly/crud.test.ts b/test/nightly/crud.test.ts
index 47caf502..747f1bd0 100644
--- a/test/nightly/crud.test.ts
+++ b/test/nightly/crud.test.ts
@@ -6,11 +6,15 @@
 import type { Location } from '@azure/arm-resources-subscriptions';
 import { AzExtParentTreeItem, createTestActionContext, randomUtils, runWithTestActionContext } from '@microsoft/vscode-azext-utils';
 import assert from "assert";
+import * as vscode from 'vscode';
 import { SubscriptionItem } from '../../src/tree/azure/SubscriptionItem';
 import { settingUtils } from '../../src/utils/settingUtils';
 import { longRunningTestsEnabled } from "../global.test";
+import { setupAzureDevOpsSubscriptionProvider } from "../utils/azureDevOpsSubscriptionProvider";
 import { getCachedTestApi } from "../utils/testApiAccess";
 
+const useAzureFederatedCredentials: boolean = !/^(false|0)?$/i.test(process.env['AzCode_UseAzureFederatedCredentials'] || '');
+
 let rgName: string;
 let locations: Location[];
 let testSubscription: SubscriptionItem;
@@ -24,21 +28,46 @@ suite('Resource CRUD Operations', function (this: Mocha.Suite): void {
         }
 
         const testApi = getCachedTestApi();
+        // Clear mock overrides that may have been set by other test suites
         testApi.testing.setOverrideAzureServiceFactory(undefined);
         testApi.testing.setOverrideAzureSubscriptionProvider(undefined);
 
+        // Re-establish the AzDO federated credential provider if running in a pipeline,
+        // since other test suites may have overwritten it with a mock provider.
+        if (useAzureFederatedCredentials) {
+            await setupAzureDevOpsSubscriptionProvider();
+        }
+
+        // Refresh the tree and wait for any pending tree operations to settle.
+        // This avoids a race condition where a background tree refresh (triggered by
+        // the logIn command in global.nightly.test.ts) cancels our getChildren() call
+        // via the shared cancellation token in AzureResourceTreeDataProvider.
+        await vscode.commands.executeCommand('azureResourceGroups.refresh');
+        await new Promise(resolve => setTimeout(resolve, 2000));
+
         const subscriptionTreeItems = await testApi.compatibility.getAppResourceTree().getChildren() as unknown as SubscriptionItem[];
-        if (subscriptionTreeItems.length > 0) {
-            const testContext = await createTestActionContext();
-            testSubscription = subscriptionTreeItems[0] as SubscriptionItem;
-            const context = {
-                ...testContext,
-                ...testSubscription.subscription,
-                environment: structuredClone(testSubscription.subscription.environment)
-            };
-            locations = (await testApi.testing.getLocations(context)).slice(0, 5); // limit to 5 locations for test speed
+
+        // Filter to actual SubscriptionItems (exclude sign-in/placeholder items).
+        const actualSubscriptions = subscriptionTreeItems.filter(
+            (item): item is SubscriptionItem => !!(item as SubscriptionItem).subscription?.subscriptionId
+        );
+
+        // if we can't find any subscriptions, then something is wrong with the test setup (e.g. auth failure), so skip the tests rather than fail them
+        if (actualSubscriptions.length === 0) {
+            this.skip();
+            return;
         }
 
+        const testContext = await createTestActionContext();
+        testSubscription = actualSubscriptions[0];
+
+        const context = {
+            ...testContext,
+            ...testSubscription.subscription,
+            environment: structuredClone(testSubscription.subscription.environment)
+        };
+        locations = (await testApi.testing.getLocations(context)).slice(0, 5); // limit to 5 locations for test speed
+
         rgName = randomUtils.getRandomHexString(12);
     });
 
diff --git a/test/utils/azureDevOpsSubscriptionProvider.ts b/test/utils/azureDevOpsSubscriptionProvider.ts
index a73ac7e8..d15ec83c 100644
--- a/test/utils/azureDevOpsSubscriptionProvider.ts
+++ b/test/utils/azureDevOpsSubscriptionProvider.ts
@@ -43,6 +43,14 @@ export async function setupAzureDevOpsSubscriptionProvider(): Promise<void> {
     // Create the provider instance now so we can return it synchronously
     const provider = await factory();
 
+    // Sign in to establish the token credential.
+    // This must be done before the provider can return subscriptions.
+    const signedIn = await provider.signIn();
+
+    if (!signedIn) {
+        throw new Error('Failed to sign in with Azure DevOps federated credentials');
+    }
+
     // Set the override via the test API
     const testApi = getCachedTestApi();
     testApi.testing.setOverrideAzureSubscriptionProvider(() => provider);