Hi @Dinesh kumar ,
Agree with @Robert Sparnaaij [MVP] .
As I know, it is normal and by design that /resetnavpane Command-line will clear and regenerate the Folder Pane(including your shared calendar folders) for the current profile. And Exchange help syncs these changes to your OWA. To get these shared calendars back, you might need to re-accept the shared calendars invitations.
For more information about other command-lines, please check: Command-line switches for Microsoft Office products.
Hope this can be helpful.
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