outlook 2010 keeps crashing

I am using MS Outlook email from a long time. I use pst password for protecting my all email data. But after some time, MS Outlook shows the wrong password. I do not understand right now how to unlock my pst password

Fewdays ago, I was in need to export .OST file to a .PST file and I tried the below mentioned procedure of this blog; https://support.office.com/en-us/article/Export-or-backup-email-contacts-and-calendar-to-an-Outlook-pst-file-14252b52-3075-4e9b-be4e-ff9ef1068f91 I have personally noticed that...