How to Fix “Hotmail.ost Is Not an Outlook Data File” Error
Outlook.com was formerly known as Hotmail.com. It is a free email service provided by Microsoft. A user can configure their Hotmail.com account on Microsoft Outlook email client like any other IMAP, POP3 email service. For this, an additional plug-in called “Microsoft Outlook Hotmail Connector” is required. The entire mailbox data is saved on an Offline Data Storage File called OST. This file has the extension ‘.ost’ and is a replica of the mailbox on the mail server. It is saved on the local computer under the Outlook mail folder.
An OST file is also generated for Hotmail accounts. This file has the name Hotmail.ost. Sometimes, users face the error “Hotmail.ost is not an Outlook data file” despite having the Hotmail connector. Therefore, in this post, we have discussed manual solutions for resolving the error. Before, that let us discuss the reasons behind the error.
Possible Reasons for Hotmail.ost Is Not an Outlook Data File Error
Following are some of the possible reasons for the error message: “Hotmail.ost is not an Outlook data file”:
- Outlook profile has been recently deleted
- MS Outlook has been uninstalled
- Corruption in the OST file
- Issue with the Hotmail connector
- Outlook running in Compatibility mode
- Running older version of Hotmail connector
At situations like this, many errors may be generated like ‘Hotmail OST is not an offline folder’, ‘Hotmail OST cannot be accessed’ or ‘OST cannot be opened’. The following segment describes possible solutions to fix these errors.
Methods to Remove Error Hotmail OST Cannot be Accessed
Following are the possible solutions to rectify the error regarding Hotmail and Outlook.
Solution 1: Re-install Microsoft Outlook Hotmail Connector
This solution is specific to removing errors as if Hotmail OST is not an MS Outlook data file. Once the Microsoft Outlook Hotmail Connector is removed, an issue cultivating from it will be removed as well.
- At First, Delete Hotmail profile configured on Outlook
- Next, uninstall the Microsoft Outlook Hotmail Connector
- Now, close Outlook
- After that, delete the OST file that was creating problems thus far
- Having done that, reinstall the latest version of Microsoft Outlook Hotmail Connector
- At last, configure Outlook again with a new profile. A new OST will be created that will not create errors anymore.
This is a proven solution and has worked for many users. However, at times, this solution may not be able to resolve some issues pertaining to Hotmail.ost is not an Outlook data file. Move to the next solution and try to resolve the issue.
Solution 2: Check If Outlook is in Compatibility Mode
At times, Outlook may be running in compatibility mode. This may generate an error like ‘Hotmail OST is not an offline folder’. In order to resolve Hotmail OST not an MS Outlook file error issue following steps should be followed:
- At first, Go to C: >> Program files >> Microsoft Office >> Office14
- Find there Outlook.exe file and Right-click on it
- Next, click on Properties and go to the Compatibility Tab
- Now, uncheck the compatibility mode box and click OK
This is one of the solutions provided by Microsoft experts on one of their community pages. If this does not resolve Hotmail OST not an offline folder error, then move to the next step.
Solution 3: Alternative Solution to Fix Error Hotmail.ost is not an Outlook data file
At times, the suggested manual solutions may not work for some reasons. Even re-installing Outlook could not find the solution of fixing error ‘Hotmail OST not a Microsoft Outlook data file’. in such situations, alternative solutions can be adopted like using the free OST Viewer Tool. This is a completely free of cost solution provided for Outlook users facing issue with Hotmail.ost is not an Outlook data file. It is a reliable and efficient solution to recover damaged data and Open OST File.
Bottom Line
Hotmail.com, now Outlook.com is a free email service that can have issues while configuring on MS Outlook email client. Errors like “Hotmail.ost is not an Outlook data file” is faced by many users who use Hotmail on Outlook. This error can be rectified by following the given solutions in this post. If nothing else works, users can choose to download the freeware OST Viewer Tool. Using the tool a user can preview all his mailbox contents in an Outlook-like interface. It is easy to use.