A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data
This behavior aligns with other issues reported in Office/Excel build 2604. In similar cases, the problem was identified as a regression introduced in that build and was reported to the product team for investigation.
For environments where the Favorites/pinned items behavior is business‑critical, the recommended mitigation is to temporarily roll back affected clients to the previous build (e.g., 2603) where normal behavior is restored, and then move forward again once a fixed build is available in the chosen update channel.
Because other fixes are also present in build 2604, any rollback decision should be scoped and tested first (for example, on a pilot group) before applying across the domain.
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