Microsoft has started to roll out a change in the functioning of email signatures.
If you are impacted, two solutions are available to you:
Implement a temporary solution proposed by Microsoft
If you choose the temporary solution proposed by Microsoft, here is the procedure to follow:
Manually disable the roaming signatures feature in Outlook.
To manually disable the roaming signatures feature in Outlook:
1️⃣ Launch RegEdit
Launch RegEdit (registry editor).
2️⃣ Navigate to:
HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\Setup\
3️⃣ Select DWORD (32-bit) Value
Right-click anywhere in the right panel, select New, then select DWORD (32-bit) Value.
4️⃣ Enter the name of the DWORD as:
Enter the name of the DWORD as DisableRoamingSignaturesTemporaryToggle and press [Enter].
5️⃣ To modify the value you can:
Either right-click on the option DisableRoamingSignaturesTemporaryToggle and select Modify
Or double-click on the button DisableRoamingSignaturesTemporaryToggle.
The Edit DWORD (32-bit) Value window appears:
In Value data, enter the value 1.
6️⃣ Save the changes
Click OK to save the changes and close the window.
7️⃣ Restart Outlook
Restart Outlook for the change to take effect.
8️⃣ Alternative REGEDIT path
If it still doesn't work, you need to access this path (or create it) and then create the key DisableRoamingSignaturesTemporaryToggle:
HKEY_CURRENT_USER\SOFTWARE\Policies\Microsoft\Office\16.0\Outlook\Setup