If you want to work on Outlook but cannot open Outlook because the OST file is in use and cannot be accessed. Want to resolve this problem? Then continue reading this article. In this article, we are going to solve the Outlook error “OST file is in use and cannot be accessed”.
Outlook is an email client and it allows you to send and receive email messages. It uses two file formats which are OST and PST to store data. Outlook uses an OST file when you have an Exchange account and want to work offline. This file is create when cached exchange mode is enable in MS Outlook. When Outlook is configure in this way, you can see all emails without internet connectivity and once you go back online, all your emails will be synchronize with the Exchange Server again.
However, sometimes Outlook crashes during synchronization with Exchange server because of poor network connection or power failure then the following error message may appear-
C:\Users\User\AppData\Local\Microsoft\username\username.ost is in use and cannot be accessed.
Reasons Behind the Outlook Error
If you are facing the issue “The OST file is in use and cannot be accessed in Outlook”, there may be several reasons behind this error. Some of them are-
- Synchronization issue between Outlook OST file and Exchange server
- Problem with network connectivity
- Conflict between Outlook and other applications
- Many users trying to access the same OST file at a time
- Suddenly shutdown of the system
- Orphaned OST file
Methods to Solve Error “The OST File is in Use and Cannot be Accessed”
Sometimes when you want to open an OST file but cannot open that and you get an error message “The OST file is in use and cannot be accessed in Outlook”. Then, there are various manual and professional methods to solve this error. We will explain all methods one by one-
Manual Method to Solve Outlook Error “The OST File is in Use and Cannot be Accessed”
There are four manual methods to solve the error: the OST file is in use and cannot be accessed in Outlook. Which are- Restart your system and router, Terminate outlook and related programs, Disable Cached Exchange Mode and Export OST files into reliable format. Here, we explain all these methods step by step-
1. Restart Your System and Router
When Outlook cannot open your OST file and show an error message. Firstly, Restart your system and again connect the system with the network. Sometimes it helps you to solve this error.
2. Terminate Outlook and Related Programs
If the above method does not help to solve the problem then you can try to terminate Outlook and related programs. Follow these steps to close the background running Outlook applications.
- Type the Task Manager in Window Search bar and open it
- Now, Select the Process tab
- Look for anything: Communicator, Outlook, Lync, UCMAPI. If you get any items related to that, select them and click on End Task button
- At last, Shut Down your system and again Restart to save the changes
3. Disable Cached Exchange Mode
If the above methods do not help you to fix the error, then you can try to disable the cached exchange mode to solve the issue.
- Firstly, Open the Outlook on your system
- Go to the File menu in the upper left corner
- Select Account Settings and go to Email tab to select your account
- Now, click on the Change tab
- After that you will see Offline Settings
- Uncheck the box of Cached exchange Mode to disable it
- At last, Restart the Outlook to save the changes
Note: if the error is not solve then back turn ON the cached exchange mode
4. Export OST File into Reliable Format
There are two ways to export an OST to another file format: one is the Import/Export option and another is a third party tool. You can manually export the OST file into reliable format using the Import/Export feature of MS Outlook. The steps to exporting OST file are-
- Firstly, Open MS Outlook application
- Go to File menu and then Open & Export and select Import/Export option
- Select Export to a file and click on Next
- Now, select Personal Storage Table File format and click on Next button
- Choose the folder from which to import items
- After that, select the destination folder to save the resultant file
- At last click on Finish button
You can convert your OST file in PST format using this method. But the method has some limitations. It is such a time consuming process. You cannot convert orphaned OST file. To neglect these limitations we use alternative method to solve the error “The file username.ost is in use and cannot be accessed”.
Expert Solution to Solve Error “The OST File is in Use and Cannot be Accessed”
We all know that manual methods have some drawbacks. So, we use a third party tool to complete this task. SysTools OST to PST Converter is the most reliable and effective tool to solve this issue. The tool converts the OST files in multiple file formats such as PST, EML, MSG, MBOX etc. It can easily convert orphaned or inaccessible and large sized OST files. The software has many advanced features such as a date filter to select a particular file. The tool can easily convert OST to PST without Exchange Profile or Server Connectivity.
Features of the Tool
- Convert OST files in multiple file formats such as PST, EML, MSG, MBOX etc.
- Export into document format such as PDF, CSV, HTML, TXT etc.
- Convert OST to PST without any limitations
- Easily converts inaccessible or orphaned OST file
- Tool supports latest version of Windows OS
Conclusion
In this article we have discussed the procedures to solve Outlook error “The OST file is in use and cannot be accessed”. We explained the manual and professional methods to fix this issue. However, you can use any of them to make your OST file accessible.
Also Read: How to Find Missing Outbox Folder Outlook
