Hi,
Does this issue happen to all emails or just emails with the special email signature? What if we try switching to another signature?
When replying or forwarding, are you using Plain Text format? what if we try switching to HTML format under
Format Text tab?
Does the issue continue if we try forwarding/replying in OWA? In addition, please also check whether this issue continue when testing in Outlook safe mode. To do this, press Windows key + R to open the Run command, type
outlook /safe and press Enter.
Regards,
Steve Fan
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