Fix New-MailboxExportRequest Error: Unable to Open PST File – Access to the Path Is Denied
For Exchange administrators, the New-MailboxExportRequest cmdlet is one of the primary tools used to export mailbox data into PST files. It plays an important role in mailbox backups, data archiving, compliance requirements, and migration projects. Despite its usefulness, administrators often encounter the following error during the export process:
“New-MailboxExportRequest: Access to the path is denied”
This issue can appear even when the Exchange Management Shell is launched with administrative privileges. Fortunately, the error is usually related to permissions or configuration settings rather than problems with the mailbox database or Exchange Server installation.
Before applying a solution, it is important to understand how Exchange handles mailbox exports behind the scenes.
How Exchange Processes PST Export Requests
When an administrator submits a mailbox export request, Exchange does not execute the operation using the credentials of the logged-in user. Instead, the request is handled by the Mailbox Replication Service (MRS), which is responsible for processing mailbox moves and export tasks.
Because MRS operates as a service account, several requirements must be met for the export to succeed.
PST Files Must Be Saved to a Shared Network Location
Exchange does not support exporting mailbox data directly to a local drive path such as C:\Exports or D:\PSTFiles. The destination must be a valid network share using a UNC path (for example, \\ServerName\PSTShare\User.pst).
Exchange Trusted Subsystem Requires Permissions
The export process runs under the Exchange Trusted Subsystem security group. This group must have the necessary permissions on the shared folder where the PST file will be created. If the required access is missing, Exchange immediately returns an access-denied message.
Mailbox Export Rights Are Not Assigned by Default
Even users with administrative privileges in the domain cannot perform mailbox exports unless they have been assigned the appropriate Exchange Role-Based Access Control (RBAC) permission. Specifically, the Mailbox Import Export role must be granted before export requests can be executed successfully.
Understanding these requirements helps identify the exact reason behind the error and makes troubleshooting much easier.
Once you understand why the error occurs, the next step is to configure Exchange and Windows permissions correctly. The following process will help you eliminate the “Access to the path is denied” issue and successfully export mailbox data to a PST file.
Stage 1: Grant Mailbox Export Permissions
Exchange restricts mailbox export operations through its Role-Based Access Control (RBAC) framework. Therefore, the account running the export request must have the appropriate role assigned.
Verify Existing Role Assignments
Open Exchange Management Shell and execute the following command:
Get-ManagementRoleAssignment -Role “Mailbox Import Export”
If your administrator account is not listed in the output, assign the required role using:
New-ManagementRoleAssignment -Role “Mailbox Import Export” -User “YourAdminUsername”
After assigning the role, close the current Exchange Management Shell session and launch a new one. The permission changes will not take effect until a fresh session is started.
Stage 2: Create a Shared Export Location
Exchange mailbox exports cannot be directed to local folders. Instead, the destination must be a shared folder accessible through a UNC path.
Configure a Shared Folder
- Create a folder such as
C:\MailboxExports. - Open the folder’s Properties.
- Select the Sharing tab.
- Click Advanced Sharing.
- Enable Share this folder.
- Save the generated network share path, which will resemble:
\\ServerName\MailboxExports
This shared path will later be used in the mailbox export command.
Stage 3: Assign Share-Level Permissions
A common reason for export failures is insufficient permissions on the shared folder.
Grant Access to Exchange Trusted Subsystem
- Open Advanced Sharing and click Permissions.
- Select Add.
- Enter Exchange Trusted Subsystem and validate the name.
- Grant Full Control permissions.
- Optionally add your administrative account with the same permission level.
- Save the changes.
These permissions allow Exchange services to create and write PST files within the shared directory.
Stage 4: Configure NTFS Security Rights
Share permissions alone are not enough. The underlying Windows file system permissions must also permit Exchange to access the folder.
Update Security Settings
- Open the folder’s Properties.
- Navigate to the Security tab.
- Click Edit followed by Add.
- Add the Exchange Trusted Subsystem group.
- Assign the following permissions:
- Read
- Write
- Modify
- Read & Execute
- List Folder Contents
- Apply the settings and close the dialog boxes.
Both Share and NTFS permissions must be configured correctly for the export operation to succeed.
Run a New Mailbox Export Job
After completing the permission setup, start a fresh Exchange Management Shell session and submit a new export request.
New-MailboxExportRequest -Mailbox “john.doe” -FilePath “\\MailServer01\MailboxExports\john_doe.pst”
If the configuration is correct, Exchange will create the export request and begin processing it in the background.
Track Export Activity
Mailbox exports are processed asynchronously. As a result, the PST file may not appear immediately after the command is executed.
Use the following command to review the progress:
Get-MailboxExportRequest | Get-MailboxExportRequestStatistics
Common status values include:
- Queued
- InProgress
- Completed
If an export does not finish successfully, detailed diagnostics can be obtained using:
Get-MailboxExportRequest -Status Failed | Get-MailboxExportRequestStatistics | Format-List Report
The generated report often reveals the exact reason behind the failure.
Additional Troubleshooting Tips
If the export continues to fail despite proper permissions, consider the following checks.
Remove Obsolete Export Requests
Old mailbox export jobs can occasionally create conflicts with new requests. Cleaning up completed or failed jobs may help.
Get-MailboxExportRequest -Status Completed | Remove-MailboxExportRequest
Get-MailboxExportRequest -Status Failed | Remove-MailboxExportRequest
After removing outdated requests, create a fresh export job.
Confirm the PST File Name
Ensure that the destination file ends with the .pst extension. Incorrect file names, invalid paths, or formatting mistakes in the UNC location can prevent Exchange from creating the output file.
Check Storage Capacity
Insufficient disk space on the destination server can interrupt the export process. For example, exporting a 50 GB mailbox to a location with only 25 GB of available storage will likely result in a failed operation. Always verify that adequate free space exists before initiating large mailbox exports.
Final Thoughts
In this write-up, we will explore multiple methods to resolve the “New-MailboxExportRequest Unable to Open PST File: Access to the Path Is Denied” error. You can review the entire guide and choose the solution that best fits your requirements. Before proceeding with any troubleshooting method, it is recommended to create a backup of your PST files to prevent accidental data loss.
For a secure and reliable backup process, you can use CubexSoft PST Converter for Mac & Windows. This advanced utility allows users to export and migrate PST data to more than 15 file formats and email services, including PDF, MBOX, CSV, Yahoo Mail, Gmail, Office 365, OLM, and many others. With its user-friendly interface and versatile conversion options, the tool ensures safe and efficient management of PST files.
