If the quick fixes don't work, the issue may be related to how Windows 11 handles notifications and system tray elements: YouTube·AarohanTechSol Fix Windows Calendar Not Showing Full Month In Windows 11
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Here’s a helpful guide you can use or share: windows 11 calendar not showing full month
Newer Windows 11 updates have added a larger clock that includes seconds. If you also have additional world clocks enabled, they take up valuable space, forcing the calendar into a truncated "split" view. If the quick fixes don't work, the issue