Fix Outlook mobile signature after switching accounts

If your Outlook mobile signature disappeared or shows the wrong account after you switched accounts, the cause is usually either the app’s per-account signature setting (local) or a server/IT policy that overrides client signatures. Start with a short triage to find whether the signature lives in the app or is applied by the mail server. Then follow the matching fix: reassign or copy the signature, clear cache or reinstall, or ask IT to change a server rule. These steps apply to recent Outlook mobile builds on iPhone and Android in 2026; update the app from the App Store or Play Store before you start.

Symptom: what you see and when it happens

Answer: You see a blank signature, a signature from a different account, or an uneditable company footer. These changes commonly happen right after you switch accounts, re-add an account, or apply an Intune/Endpoint Manager profile.

You might see one or more of these:

• Your signature field is empty when composing new mail on mobile.

• The signature shows text or a footer belonging to a different account.

• A company footer appears in every message and you cannot edit it; the app may show a message that the signature is managed.

• HTML formatting, images, or links look broken or are removed, especially in replies and forwards.

These issues usually appear immediately after you switch the active account in the Outlook mobile selector, re-add an account, or a device profile is applied.

Before you start (scope, permissions, safe checks)

Answer: This guide is for Outlook mobile on iPhone and Android. You need access to the affected device and mailbox. If your mailbox is employer-managed, you may need IT permission to change server-side settings.

• Check the app version and update if it is months out of date.

• Save your signature to a secure note or company vault before clearing storage or reinstalling.

• If a settings message says the signature is managed by your organization, collect evidence and contact IT rather than reinstalling.

• Re-enrolling or re-adding a device can reapply managed settings from Intune/Endpoint Manager.

Quick triage: is the signature app-side or server-side?

Answer: Do quick checks that take a minute each to see whether the signature is stored in the app or added by the server. The result tells you which repair path to use.

1. Check the per-account signature field in Outlook mobile for the account you switched to.

Outlook (iOS) → Profile icon → Settings (gear) → Account name → Signature

Outlook (Android) → Profile icon → Settings (gear) → Account name → Signature

2. From the mobile account, send a short test message to an address you control with a clear subject.

3. From Outlook on the web or the desktop client using the same mailbox, send a second test message with the same subject.

4. Compare the two received messages:

• If mobile and web both contain an identical footer you didn’t create, the server or an admin policy is applying the signature (server-side).

• If mobile is blank but web has your personal signature, the app’s local signature is missing or misassigned (app-side).

• If mobile shows a signature that belongs to another account in the app, the signature data is stored under that other account (app-side).

Confirm where signatures are stored and which account is active

Answer: Outlook mobile keeps a separate signature per account inside the app; Exchange/Intune can also inject or block client signatures. Confirm the active account and copy the signature before you edit anything.

1. Open Outlook mobile and select the account so it appears at the top.

2. Open Settings, pick the account, and read the Signature field.

Outlook (iOS/Android) → Profile icon → Settings (gear) → Select account → Signature

3. If the signature field shows a message like "signature is managed by your organization," stop and collect evidence for IT.

4. Copy the signature text or HTML to a secure note so you can restore it later.

• If you have multiple Outlook profiles, repeat this check for each profile that might hold the signature.

Fast fixes for app-side problems (reassign, refresh, reinstall)

Answer: Try fixes from least to most disruptive: reassign the signature, refresh the app, then reinstall. Always back up the signature before destructive steps.

If the signature exists under another account in the app:

1. Open Settings and find the account that currently holds the signature.

2. Copy the entire signature to your clipboard or a secure note.

3. Switch to the target account and paste the signature into that account’s signature field.

4. Save and send a test message from mobile to confirm the correct signature is used.

If the app shows a blank signature due to cache or local corruption:

1. On Android, clear the app cache.

Settings → Apps → Outlook → Storage → Clear cache

2. On iOS, use Offload App to refresh without removing documents, or delete and reinstall if Offload isn’t available.

3. Reopen Outlook, sign in, and check the per-account signature fields before adding other accounts back.

If cache clear or reinstall did not help:

1. Remove and re-add only the affected account after you saved the signature text.

2. After re-adding, check the signature field immediately before server policies reapply and send a test message.

What to expect if these fixes fail:

• If the app shows the correct signature but received mail shows a different footer, the issue is server-side.

• If the app repeatedly loses the signature after re-enrollment, the device management profile is reapplying settings; contact IT.

Restore or transfer a signature created on another device

Answer: Copy and paste the signature from the original device or Outlook on the web. If the signature is HTML-heavy, copy the HTML source and keep a plain-text fallback.

1. On the original device or Outlook on the web, open the signature editor and select the full signature.

2. Copy the text and any inline images. If the signature uses complex HTML, copy the HTML source into a secure note.

3. On mobile, open the target account’s Signature field and paste. Send a test message.

If the original signature is server-injected and you didn’t create it:

1. The server-side template must be changed by an admin. Collect evidence and ask IT to restore or allow a client-side signature for your mailbox.

When the signature is controlled by your organization (server-side or Intune)

Answer: If both web and mobile show the same footer you didn’t create, or the app shows a management message, the signature is server-controlled. Collect evidence and ask IT to change the rule or profile.

1. Capture these evidence items before contacting IT:

• Screenshot of mobile signature settings showing the account selector and signature field.

• Screenshot of any message that says the signature is managed.

• Screenshot of the app About/version screen.

2. Save the full received messages from mobile and web as .eml files or copy the bodies, and export the full message headers for one received message.

3. Ask IT whether a transport/mail flow rule, an Exchange Online signature policy, or an Intune/Endpoint Manager profile applies the footer.

4. If you need a client-side mobile signature, request an exception or a profile change. If IT must enforce a company footer, keep a short client-side marker that won’t conflict with the server footer.

What to expect from IT:

• Admins can exclude mailboxes from transport rules or change rule order, subject to company policy.

• If the device is managed, admins may need to change the device profile in Endpoint Manager rather than a mailbox rule.

If IT cannot or will not change the server policy, keep a plain-text mobile signature you control and accept that the server footer will also appear in sent messages.

Fix HTML formatting loss and signatures missing in replies/forwards

Answer: HTML formatting can be lost because replies convert to plain text, device policy forces plain text, or mobile blocks external images. Test new messages and replies to find the cause.

1. Compose a new message on mobile and confirm the compose toolbar shows formatting options like bold, italic, and link.

2. Reply to your test message and check whether the signature appears and if formatting is preserved.

3. If replies are plain text but new messages support HTML, use a plain-text fallback for replies or ask IT to change the policy.

4. For missing images:

• Avoid externally hosted images that require remote loading; mobile often blocks these.

• Use a hosted image on a trusted company domain if your environment allows it, or keep images small and embedded where corporate policy supports it.

If formatting still breaks:

• Paste a simplified HTML-free version into the mobile signature and keep the full HTML in your saved canonical copy so you have a reliable fallback for mobile recipients.

When to re-add the account, contact IT, or escalate to Microsoft Support

Answer: Choose the least disruptive action that matches the triage result: re-add for client corruption, contact IT for server enforcement, and escalate to Microsoft if IT finds no server policy and the issue persists.

• Re-add the account only for app-side corruption after you backed up the signature. Re-adding clears local settings and can resolve client corruption.

• Contact IT if you confirmed server-side enforcement: provide the evidence you collected and open a helpdesk ticket.

• Escalate to Microsoft Support if IT confirms no server rule or device policy explains the behavior and the issue persists across networks and devices.

Before escalating, gather the evidence listed in the next section so Microsoft or IT can diagnose without repeated requests.

What to collect before contacting IT or Microsoft Support

Answer: Collect screenshots, saved test messages, headers, and a short log of your troubleshooting steps. This speeds diagnosis and avoids back-and-forth.

• Screenshot: mobile signature settings showing the account selector and signature field.

• Screenshot: any message in settings that says the signature is managed.

• Screenshot: app About/version screen.

• Two received test messages saved as .eml files or copied text: one sent from mobile, one from web/desktop.

• Full message headers from one of the received test messages.

• A short list of steps you already tried: copy signature, cleared cache, reinstalled, re-added account, etc.

Provide these items with your ticket and describe the exact account names, device OS, and app version so IT can check transport rules, mail flow, and device profiles without extra requests.

Verify the fix

Answer: Test the same scenarios that failed before. Send and reply from mobile and web, and check signatures immediately after reinstall or re-add.

1. Send a new message from mobile to your test address; expected: the received message shows the signature you set in the app (or the server footer if server-controlled).

2. Reply to the received test message from mobile and from the web client; expected: signature appears as intended for new messages and replies where applicable.

3. If you reinstalled or re-added the account, check the signature immediately after sign-in and before reapplying managed profiles.

If results are not as expected:

• If the client shows your signature but the received mail shows a different footer, return to the server-side section and contact IT.

• If the app repeatedly loses the signature after re-enrollment, escalate to IT to adjust the device profile.

Prevent recurrence

Answer: Back up your signature, keep a canonical HTML copy and a plain-text fallback, and check the per-account signature after switching accounts. These small habits reduce future problems.

• Always copy your signature to a secure note before removing or re-adding an account.

• Keep one canonical copy of your HTML signature plus a plain-text fallback.

• If your device is managed, ask IT whether settings reapply when you re-enroll and keep screenshots of approved settings.

• When switching accounts in Outlook mobile, check the signature field right after switching so you notice misassigned signatures before sending mail.

Conclusion

Follow the triage checklist first to decide whether the problem is app-side or server-side. For app-side issues, back up and reassign the signature, clear cache or reinstall as needed, and back up your signature before removing accounts. For server-side enforcement, collect the evidence described above and work with IT to change a transport rule or device profile.