Hi @Nur Hossain ,
in exchange node 1 out of 2 facing issue 'Microsoft Exchange Writer showing unstable.
May I know if there are any other error messages when this occurs?
Based on my research regarding this kind of situation, please try restarting the Information Store Service on the problematic server and see if there would be any improvement.
Besides, it's also recommended to contact the support for Veritas NetBackup to confirm if they have seen similar reports from other users and whether they could provide any possible solutions on this.
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