What is nst in outlook?

An . NST file is a local copy of any Microsoft 365 Group mailboxes linked to that Microsoft hosted account. Each Microsoft 365 Group has a shared mailbox and calendar, which Outlook desktop synchronizes to the . NST for faster and offline access.

If you are an Outlook user then I am quite sure you must be aware of OST and PST file formats but fewer users know about NST file format of MS Outlook. They have only one question in their mind that What is an NST file format? Well, in this blog I’ll tell you about NST file and where are they located. I would be also covering the creation of an NST file and how to open NST file in Outlook.

NST is basically an extension of Outlook file which is stored on the local machine whenever a user configures Office 365 in Outlook. MS Outlook Synchronizes the local copy of Office 365 and stores it on the PC in a group storage table also known as GST files. The reason for creating the GST file is to allow the user to work in an offline mode on Office 365 as OST works for MS Outlook. In order to clear your facts, both these files OST and GST are stored in the same folder.

Outlook Slider manages and controls the data synchronized in the GST file with .nst extension. The NST files usually stores conversations in groups and calendars whereas the OST file stores mailbox items and other folders into it. Whenever a user accesses IBM Lotus Notes using Outlook Connector then it creates NST files on the local machine.

The NST files are created automatically whenever you configure Office 365 to Outlook because all the cached data of Office 365 is stored in NST file format.

As I have told you earlier that NST files are the cached offline files of Office 365 and therefore they are always in an unreadable form. In order to view NST files in Outlook, you need to convert it into PST and then import PST file in Outlook.

Once you save the OST file as PST, you can import it into your Outlook account and ultimately open NST file in Outlook without losing a single data.

Do you want to know what is NST file in Outlook? Don’t be much concerned about thinking this question. As in this article, you will get complete information about *.nst file extension and how to make it usable for different purposes.

If you use Microsoft Outlook, you are probably familiar with the terms OST (Offline Storage Table) and PST (Personal Storage Table). But some of Outlook users don’t know what kind of file is NST.

Additionally, the Microsoft Outlook Connector for IBM Notes Add-in generates an NST file that can be used to connect to HCL / IBM / Lotus Notes via Microsoft Outlook. NST files generated by Outlook Connector can be used to store Lotus Notes email messages and other critical data on a local computer. The NST file format is similar to the OST file format.

Follow the given steps for generating Outlook Data File NST.

Option 1 – Download Free NST File Viewer Tool that is capable to view GST (Group Storage Table) file data in the absence of Microsoft Outlook. This application permits to read complete data of NST files i.e., Emails, Contacts, Calendars, etc.

Option 2 – Download NST to PST Converter that allows to change Outlook data file .nst into 30+ formats. Therefore, this is one of the best ways to use NST files with multiple email clients, email services, and standard file extensions.

• Locate the NST file in your PC.
• Make a Right-Click on it and then select Properties.
• Under the General tab Change the file extension from .
• Once you change the File name, open the tool you downloaded.
• Add OST file into the software which you have renamed.

An .NST file is in the same folder as a .OST file for a Microsoft 365 hosted mailbox (a Microsoft 365 plan with Exchange Online).

The usual location is C:\Users\\AppData\Local\Microsoft\Outlook

Unhelpfully, the .NST file is given the same text label as the main .OST file “Outlook Data File”. That’s correct but no help understanding what the two files are for.

Outlook .OST files are local copies of online mailboxes, most commonly Exchange Server mailboxes but also IMAP connections (common for Gmail).  .PST files are used to keep items for POP connections and other local Outlook data storage.

All three file types (OST, PST and NST) are essentially the same, as complex and often large database files.

An .NST file is a local copy of any Microsoft 365 Group mailboxes linked to that Microsoft hosted account.

Each Microsoft 365 Group has a shared mailbox and calendar, which Outlook desktop synchronizes to the .NST for faster and offline access.

There’s a single NST file for each Microsoft 365 hosted mailbox, the NST has the data for all Groups that mailbox has joined.

The presence of .NST files can be confusing for anyone who hasn’t used Microsoft 365 Groups or even know they exist.

According to Microsoft the .NST file is created “The first time you access a Group in Outlook,” but that’s clearly not happening.

This Office Watch article was prompted by questions from people wondering about the .NST files and are even more confused when told they relate to Groups “What the #%@$ are Groups”

Sure enough, my own NST file was created over a year ago (August 2021) at the same time as the main .OST file for that mailbox.  Even though the first use of Groups for that mailbox was only yesterday!

Despite what Microsoft says, a small .NST file appears to be created automatically with the setup of a new Microsoft 365 account in Outlook desktop.

There’s no need to backup either .OST or .NST files (except in some very exceptional long-time offline situations).

Both files are synchronized copies of the online mailbox saved on Microsoft’s cloud servers or elsewhere.  If lost, Outlook desktop can recreate them from the online data.

Yes, but it won’t do you much good. Don’t touch .NST files, leave them be.

They aren’t doing any harm and deleting them won’t save any disk space because Outlook will recreate them automatically.

If disk space is very limited, you could free up space by compressing the .NST files using NTFS.  We do NOT recommend doing this because there’s a small performance hit and there are usually better options to free up disk space.

If you insist, close down Outlook completely, go to the folder with the .NST file, right-click on the file, go to Properties | Advanced | ‘Compress contents to save disk space’.