The most common symptom is a calendar that stubbornly reverts to its original color scheme after every restart, or ignores custom repeat patterns you painstakingly set. Users also report missing event tags, unresponsive drag‑and‑drop, and vague error messages when they try to import external .ics files. These glitches act like a silent alarm, warning that the underlying configuration file is either corrupted or still running the legacy defaults from the original 1995 installation.
Behind those symptoms lies a second, less obvious cause: the Calendar 95 profile is often duplicated across multiple user accounts, each with its own hidden registry keys. When a user updates one profile, the others continue to read the outdated settings, creating a tug‑of‑war that manifests as intermittent freezing or lost notification sounds. Recognizing this hidden duplication is essential before any visual tweak can stick.