Hi. Help me to understand. The problem has one of the employees, he demolished mail, while maintaining files .ost. In fact there should be no problems. Always when the client connects to the Outlook (if storage was Mailbox Exchange) is automatically pulled from the mail server. But this is not happening. It draws only the contacts and everything. I looked a mailbox on a server size of 20kb. And the size of the .ost 135mb. It is logical that there is a server-mails therefore they .ost. Surfing network I found pair program conversion .ost to .pst. But they didn’t help. Are there any fast methods to do this?

It sounds like the user created a PST to store their files, instead of deleting them, correct?
The user can open Outlook but they do not receive any new email. They just see contacts, etc.
Their mailbox on the exchange server is 20kb.
The size of their OST doesn't matter. That's just Outlook's storage file on the workstation. That's where email is saved to on the workstation.
Is the user receiving new emails? Can you check the Exchange routing log to check if email is delivered to the user?
It sounds like when creating the PST file, the user deleted their Exchange account from Outlook.

commented: To restore data from OST files into outlook data file format, OST to PST conversion tool is the most appropriate tool. It allows to convert multiple O +0