Microsoft Bookings and Planner, both opt-in features, may be experiencing URLs being blocked by Microsoft Safe Links in the email messages distributed through these tools. 

Behavior: The recipient clicks on the link, producing an error message rather than opening the correct page. The error only occurs in some messages that originate in the Bookings and Planner tools. 

The IT Security Office (ITSO) has been working tickets and reports as they come in and is working with the vendor.
 
UPDATE: The ITSO has expanded our response from allowing individual blocked links to creating an exception for whole Microsoft owned subdomains that appear to be affected.

Workaround: Email recipients receiving a message in which Microsoft Safe Links produces an error can highlight the link, copy/paste the URL in their browser, or use the Safe Links decode tool (https://it.cornell.edu/decode) to access the linked pages without error.

The issue has been resolved.

Microsoft Bookings and Planner, both opt-in features, may be experiencing URLs being blocked by Microsoft Safe Links in the email messages distributed through these tools. 

Behavior: The recipient clicks on the link, producing an error message rather than opening the correct page. The error only occurs in some messages that originate in the Bookings and Planner tools. 

The IT Security Office (ITSO) has been working tickets and reports as they come in and is working with the vendor.
 
UPDATE: The ITSO has expanded our response from allowing individual blocked links to creating an exception for whole Microsoft owned subdomains that appear to be affected.

Workaround: Email recipients receiving a message in which Microsoft Safe Links produces an error can highlight the link, copy/paste the URL in their browser, or use the Safe Links decode tool (https://it.cornell.edu/decode) to access the linked pages without error.

The frequency of incorrectly blocked links has subsided, but a full fix from Microsoft is not expected until the end of the month. Continue to use workarounds as needed.

Microsoft Bookings and Planner, both opt-in features, may be experiencing URLs being blocked by Microsoft Safe Links in the email messages distributed through these tools. 

Behavior: The recipient clicks on the link, producing an error message rather than opening the correct page. The error only occurs in some messages that originate in the Bookings and Planner tools. 

The IT Security Office (ITSO) has been working tickets and reports as they come in and is working with the vendor.
 
UPDATE: The ITSO has expanded our response from allowing individual blocked links to creating an exception for whole Microsoft owned subdomains that appear to be affected.

Workaround: Email recipients receiving a message in which Microsoft Safe Links produces an error can highlight the link, copy/paste the URL in their browser, or use the Safe Links decode tool (https://it.cornell.edu/decode) to access the linked pages without error.

Microsoft is continuing to investigate the issue. Use of the workaround is still recommended.

Microsoft Bookings and Planner, both opt-in features, may be experiencing URLs being blocked by Microsoft Safe Links in the email messages distributed through these tools. 

Behavior: the recipient clicks on the link, producing an error message rather than opening the correct page. The error only occurs in some messages that originate in the Bookings and Planner tools. 

The IT Security Office has been triaging individual tickets and reports as they come in, and will continue to do so. We are also working with the vendor; they have only suggested workarounds at this point. 
 
UPDATE: the ITSO has expanded our response from allowing individual blocked links to creating an exception for whole Microsoft owned subdomains that appear to be affected. The change may take time to propagate but we expect to see improvements up by mid-afternoon.

Work around: email recipients receiving a message in which the Microsoft Safe Links produces an error can highlight the link, copy/paste the URL in their browser, or use the Safe Links decode tool (https://it.cornell.edu/decode) to access the links without error.

Troubleshooting with vendor, customer workaround provided in the meantime

Microsoft Bookings and Planner, both opt-in features, may be experiencing URLs being blocked by Microsoft Safe Links in the email messages distributed through these tools. 

Behavior: the recipient clicks on the link, producing an error message rather than opening the correct page. The error only occurs in some messages that originate in the Bookings and Planner tools. 

The IT Security Office has been triaging individual tickets and reports as they come in, and will continue to do so. We are also working with the vendor, but they have only suggested workarounds at this point.
 
Next steps: the ITSO will to expand our response from allowing individual blocked links to creating an exception for whole Microsoft owned subdomains that appear to be affected.

Work around: email recipients receiving a message in which the Microsoft Safe Links produces an error can highlight the link, copy/paste the URL in their browser, or use the Safe Links decode tool (https://it.cornell.edu/decode) to access the links without error.

Troubleshooting with vendor, customer workaround provided in the meantime