Microsoft Exchange Online Users are encountering an unexpected bug where the term “[EXTERNAL]” appears in the subject lines of their emails, despite no recent changes on their end. This issue has caused confusion among administrators who have not set up any filters or rules to add this prefix. Microsoft has confirmed that a significant number of similar reports from other customers have been received and is actively investigating the root cause with high priority. The company apologizes for the inconvenience and assures users of its commitment to resolving the matter as quickly as possible.
Marcel S., a user on Facebook, was the first to report this issue after noticing that Microsoft had automatically added “[External]” to his emails’ subject lines overnight without any prior notification or explanation from the company. Similar reports have been pouring in from various other users, leading to an influx of support cases and inquiries for further information.
Ralf E., another user affected by this bug, contacted Microsoft Support about the issue, receiving a response that acknowledged the problem and assured him it is being treated as a high-priority case. The message also noted that no recent changes on his end were responsible for the unexpected addition of the [EXTERNAL] tag to email subjects.
Exchange Online Bug Analysis from External Sources
Several tech blogs and forums have reported similar issues, suggesting a widespread problem affecting multiple organizations using Exchange Online services. Experts recommend closely monitoring the situation as Microsoft works towards resolving the issue. For more details on this topic, users can refer to reputable sources like TechRadar or CNET for updates.
Similar questions
When did the “[EXTERNAL]” tag start appearing in email subject lines?
Why is Microsoft adding this prefix without any notification to users?
Have other users experienced the same issue recently?
Is there a known cause for this bug yet?
What steps should I take if I encounter this problem with my emails?
How can I prevent external emails from being marked automatically in Exchange Online?
Has Microsoft provided an estimated time frame for resolving this issue?
Are there any workarounds available until the bug is fixed?
Can users remove the “[EXTERNAL]” tag manually from their email subject lines?
Is Microsoft planning to send out a general notification about this issue to all affected customers?