Debugging NAS connection issues
Posted by on 9 Apr 2024 12:29

MailStore Server runs as the nt authority\system account and therefore network resource requests initiated by MailStore are processed in that context rather than from your user account.

Although you can see a share as an administrator this does not guarantee that MailStore can access it.
Mapped drive letters from a user session are never available to MailStore Server as they only exist for the user that created them and only while you are logged in.

You can test MailStore's connection to your network file storage using Microsoft Sysinternal's PsExec tool to launch a command prompt as the "local system" account, allowing you to test accessing the network from a similar set of credentials as MailStore itself.

Download Sysinternals PsTools and extract the content into a directory on your hard disk.
Login to the computer where MailStore Server is installed.
Execute a command prompt as administrator.
In the command prompt, change to the directory where you extracted the PSTools.
Run the "psexec.exe" command to switch the context of the command prompt to "local system":

psexec.exe -s cmd.exe

Verify if that was successful by executing the whoami command, if successful the response will be "nt authority\system"

Try to list the files in the share using the dir command like this:

dir "\\server\share\MailArchive"

If successful, try to read the MailStoreMaster.key file using the type command like this:

type "\\server\share\MailArchive\MailStoreMaster.key"

And finally, try to create and then remove a file in the share using the following commands:

echo. > "\\server\share\MailArchive\test.txt"
del "\\server\share\MailArchive\test.txt"

All of the above commands must be successful, if any step fails you must troubleshoot that specific step individually. If you're unable to make the initial connection then you may need to authenticate to the network storage as a user, this can be done via the Windows "net use" command in this format:

net use \\server\share /user:domain\username password

In particular, use \\server\share without a trailing slash, and without any further folder structure included. If you connect successfully then repeat the above steps to confirm connectivity.

In the case of an Active Directory joined file server be sure to follow the Authorize a Computer Object documentation, checking both NTFS permissions and the share permissions.
In the case of a file server that is not part of the same Active Directory domain, or a 3rd-party NAS that does not support computer objects you can instead use the Authorizing a User Object steps in the documentation.
The "net use" command described above is the "User Object" method and therefore you may need to verify the credentials in the Configure the MailStore Server Service tool are correct.

Until you reboot MailStore may be using the session created by the command above, therefore reboot the Windows Server and check to make sure that MailStore can access the network resources as needed.

For further information on PsExec please review Microsoft's PsExec documentation.

Artikel-ID: KB20130409-0-EN (Deutsche Version)

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