You need to recover some old emails in your .ost file.
When you try to open the outlook .ost file in Outlook
and then got the message "outlook .ost file cannot be
accessed because it has been configured for use with a
different mailbox" and face the necessity to convert
all information from Microsoft Exchange (files with
the .ost extension) into files of the Microsoft
Outlook email client (.pst files) - OST2PST procedure.
SysTools Open Microsoft OST File software effectively
solves problem OST to PST Conversion. You can use the
Open Microsoft Outlook OST File tool to easily move
your messages, contacts, notes, meetings, reminders,
tasks and all other information. Open Microsoft OST
File tool work on offline file like .ost file. This
Open OST File tool use to open OST file in Outlook PST
file with complete item of OST file with time and
date. Microsoft OST to PST tool has some wonderful
feature to support all the version of Outlook 2010,
2007, 2003, 2000 & 98 etc. And it store on the Windows
operating system and make good capability to do
reliable work and it simply pick data from Exchange

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