Outlook .ost Cannot be Opened- Resolve the Error with Ease

Summary: Microsoft Outlook is one of the most widely used email clients for both personal and professional communication. It helps users easily manage their emails, calendars, contacts, and tasks. However, like any other software, it can encounter errors that affect its performance. One such frustrating issue is when users see the error message “Outlook .ost cannot be opened.” This can disrupt your workflow and leave you searching for a solution to fix the issue. In this blog, we’ll explore the reasons behind the error, its symptoms, and the best solution to resolve it using the OST Repair Tool and other troubleshooting methods. Download Now   Purchase Now

What Does the “OST File Cannot be Opened” Error Mean?

An OST file (Offline Storage Table) is a crucial file format in Outlook that stores your mailbox data offline. It keeps a copy of your mailbox on your device, so you can access your emails, contacts, and calendars, even without an internet connection. However, when you see the “ost cannot be opened” error, it means Outlook is unable to access or open this OST file, resulting in a range of issues like missing emails, inability to access contacts, or even complete data loss.

Why Does the “Outlook .ost Cannot be Opened” Error Occur?

Several factors can trigger the “OST file cannot be opened” error in Outlook. Some of the most common reasons include:

• Corrupt OST File: The most frequent cause of this issue is a corrupted OST file. Corruption can occur due to abrupt shutdowns or improper syncing with the server.
• Outdated Outlook Version: Using an outdated version of Outlook can lead to compatibility issues, making it impossible for Outlook to open the OST file.
• Incorrect Outlook Profile Settings: Misconfigured Outlook profiles or account settings can interfere with the proper functioning of Outlook and its associated OST file.
• Large OST File Size: If your OST file has expanded too large, Outlook might fail to open it, especially if the system resources are limited.
• Hard Drive Issues: Disk errors or bad sectors on your storage drive can damage the OST file, causing the error.
• Network Connectivity Problems: If there’s a network issue while syncing the OST file with the mail server, it could result in the file being inaccessible.

Symptoms of the “Cannot Open Outlook OST File” Error

When you encounter this issue, you may notice the following symptoms:

• Outlook crashes or freezes when trying to open the OST file.
• Error messages such as “Cannot open OST file” or “The operation failed” appear on your screen.
• Missing or inaccessible emails, contacts, and calendar entries.
• Slow Outlook performance, often accompanied by frequent delays or freezing.
• Outlook cannot synchronize offline mailbox data with the server.

If you are facing any of these issues, it is likely that your OST file is corrupted or there’s some other conflict preventing it from being opened.

How to Resolve the “File OST Cannot be Opened” Error?

There are multiple ways to address the “file OST cannot be opened” error. We will discuss the most effective methods below.

1. Use the OST Repair Tool (Best Solution)

One of the easiest and most effective ways to resolve the “Microsoft Outlook OST cannot be opened” error is by using a specialized tool like the OST Repair Tool. This tool is designed to repair corrupt OST files and recover inaccessible mailbox data. Whether the issue is caused by corruption, server sync problems, or any other reason, this tool can help restore the OST file and ensure smooth Outlook operation.

Quick Steps to Fix the Error “Outlook .ost Cannot be Opened“

1. Download and install the OST Repair Tool on your computer.
2. Launch the tool and select the corrupted OST file you want to repair.
3. Click on “Repair” to begin the process. The tool will scan the OST file and repair any corruption.
4. Once the repair process is complete, you can preview the recovered emails and other items.
5. Choose the desired format (PST, EML, etc.) to save the repaired file and then import it back into Outlook.

Using the OST Repair Tool is a fast and efficient way to fix the “Outlook OST file cannot be opened” issue without the need for technical skills.

2. Recreate Your Outlook Profile

If your Outlook profile is corrupted, it can prevent you from opening the OST file. In such cases, creating a new profile and reconfiguring your account might help resolve the issue. Before following any manual method it is recommended to take a backup of .ost file. Here’s how you can do that:

1. Open Control Panel and go to User Accounts > Mail.
2. Click on Show Profiles and then choose Add.
3. Create a new profile by entering the required details (such as your email address).
4. Once the profile is created, set it as the default profile.

3. Run the Inbox Repair Tool (ScanPST)

Microsoft Outlook includes a built-in tool called ScanPST.exe that can help fix minor corruption issues in OST files. To use it:

1. Close Outlook.
2. Locate the ScanPST.exe file on your computer in the following location:
• For 32-bit Outlook: C:\Program Files\Microsoft Office\OfficeXX
• For 64-bit Outlook: C:\Program Files (x86)\Microsoft Office\OfficeXX
3. Double-click the tool and follow the on-screen instructions to repair the OST file.

This tool can resolve minor corruption, but if the OST file is severely damaged, using a third-party tool may be the better option.

4. Repair Outlook Application

If none of the above solutions work to resolve the “Outlook .ost Cannot be Opened” error, try repairing Outlook. Sometimes, repairing Outlook can fix issues related to software conflicts or corruption within the Outlook application.

1. Close the Outlook application if it is currently running.
2. Open the Control Panel on your computer.
3. In the Control Panel window, click on Programs and Features.
4. Locate Microsoft Office (or Outlook) from the list of installed programs, and then click on the Change option.
5. In the new window, select the Quick Repair option and then click Repair.
6. Once the repair process is complete, restart the Outlook application and check if the issue is resolved.

5. Turn Off Conflicting Outlook Add-ins

Faulty or conflicting add-ins can sometimes cause issues in Outlook. Disabling them can help resolve the issue.

1. Open Outlook in Safe Mode by holding the Ctrl key while launching the Outlook application. This will start Outlook without loading any add-ins.
2. Once Outlook opens, click on the File tab in the top left corner.
3. Open the Outlook Options window by selecting Options from the menu.
4. In the Outlook Options window, choose Add-ins from the list on the left.
5. At the bottom of the Add-ins section, next to Manage, select COM Add-ins from the drop-down menu, then click Go.
6. In the COM Add-ins window, uncheck the box next to any add-ins that might be causing issues or conflicts.
7. Click OK to disable the selected add-ins.
8. Close and restart Outlook to check if the problem is resolved. You can enable the add-ins one by one to identify the faulty ones.

6. Update Outlook

Updating Outlook ensures you have the latest features and bug fixes, which may resolve errors such as “Outlook .ost cannot be opened.”

1. Open Outlook and go to the File tab in the top left corner.
2. In the File menu, select Office Account (or Account depending on your version).
3. Under Product Information, click on Update Options.
4. From the drop-down menu, select Update Now.
5. Outlook will check for updates and automatically download and install any available updates.
6. Once the update is complete, restart Outlook to apply the changes.

Conclusion

The “Outlook .ost cannot be opened” error can be caused by various factors, but with the right approach, it can be resolved quickly and effectively. If you encounter the “cannot open OST file Outlook 2016” issue, using the OST Repair Tool is the most efficient solution. This tool allows you to repair corrupted OST files and recover your valuable email data with ease.

By following the steps outlined above, you can fix the file OST cannot be opened error and continue using Outlook without interruptions.