How to Remove an Outlook Cached Account Without Losing Local PST Data

You need to remove an email account from Outlook but keep the locally stored PST file and its folders, contacts, and archived messages intact. Outlook caches account data in an OST file, which is tied directly to the account and becomes inaccessible after removal. This article explains how to safely remove a cached account while preserving all local PST data, including manual export steps and profile management techniques.

Understanding Outlook Cached Accounts and PST Data

Outlook creates an Offline Storage Table (OST) file for each cached Exchange, Microsoft 365, or IMAP account. The OST file synchronizes a copy of the server mailbox to your local drive. When you remove the account from Outlook, the OST file becomes orphaned and cannot be opened in any profile. The PST file, or Personal Storage Table, is a separate file type used for local archives, exported data, or manually created data files. PST files are not tied to any specific account and remain accessible after account removal.

The key distinction is that OST files are account-dependent, while PST files are independent. If you have data stored only in an OST file, you must export it to a PST file before removing the account. If you already use a PST file for archiving or local storage, that file is safe and will remain in Outlook even after the cached account is gone.

Steps to Remove a Cached Account While Keeping PST Data

Follow these steps in order. Do not skip the verification and export steps if you need to preserve any data currently inside the OST file.

1. Locate the Current PST and OST File Paths
   Open Outlook. Go to File > Account Settings > Account Settings. Select the cached account you want to remove and click Change. Under Offline Settings, click More Settings. Go to the Advanced tab. Click Outlook Data File Settings. Note the full path shown for both the PST file and the OST file. Write down these paths. Close all dialog boxes without making changes.
2. Export OST Data to a New PST File (If Needed)
   If the OST file contains folders or items you want to keep, export them now. Go to File > Open & Export > Import/Export. Select Export to a file and click Next. Choose Outlook Data File (.pst). Select the account mailbox or specific folders. Check Include subfolders. Click Next. Browse to a safe location, such as your Documents folder, and name the file. Click Finish. Do not set a password unless required.
3. Export Existing PST Data to a Separate Backup (Optional)
   If you have an existing PST file that you use for archiving, you may want to make a copy as a safety measure. Close Outlook. Open File Explorer. Navigate to the PST path you noted in step 1. Copy the PST file to a backup folder. This step is optional but recommended.
4. Remove the Cached Account from Outlook
   Open Outlook. Go to File > Account Settings > Account Settings. Select the cached account. Click Remove. Confirm the removal when prompted. Outlook will close the connection to the server and delete the OST file association. The PST files already loaded in your profile remain intact.
5. Verify That PST Data Is Still Accessible
   After removal, check the left navigation pane in Outlook. Your PST data files should still appear under their own folder hierarchy. If a PST file is missing, go to File > Open & Export > Open Outlook Data File. Browse to the PST file location and open it. The PST data will reappear in the folder pane.
6. Remove the Orphaned OST File (Optional)
   The OST file remains on your hard drive but is no longer connected to any account. Open File Explorer. Navigate to the OST file path you noted in step 1. Delete the OST file to free up disk space. Outlook will not recreate it because the account is gone.

Common Pitfalls and How to Avoid Data Loss

I removed the account and now my PST file is gone from Outlook

This happens when the PST file was associated only with that specific account profile. Open Outlook. Go to File > Open & Export > Open Outlook Data File. Browse to the PST file location and select it. The PST data will reappear. To prevent this in the future, add the PST file to a separate profile or keep it in a known folder.

I cannot open the OST file after account removal

OST files are locked to the account that created them. You cannot open an orphaned OST file in any Outlook profile. If you did not export the data before removing the account, the data is lost. The only recovery option is to reconnect the account and export the data, then remove the account again.

My exported PST file is password protected and I forgot the password

Outlook PST file passwords are not recoverable. If you set a password during export and lose it, the PST file becomes unreadable. Always store PST passwords in a password manager or avoid setting a password on archive PST files.

OST vs PST: What Each File Type Preserves

Item	OST File	PST File
File association	Tied to one specific cached account	Independent of any account
Data source	Server-side mailbox copy	Local export or archive
Access after account removal	Cannot be opened	Can be opened in any profile
Default location	%localappdata%\Microsoft\Outlook	%userprofile%\Documents\Outlook Files
File size limit	Determined by server policy	50 GB for Outlook 2019 and Microsoft 365

Removing a cached account from Outlook is safe as long as you export any OST data you want to keep and verify that your PST files remain accessible. After removal, you can continue using your PST archives in the same Outlook profile or move them to a different profile. For advanced data management, consider creating a dedicated archive PST file that is not tied to any specific account profile.