hashicorp/vagrant · error · VagrantPlugins::SyncedFolderSMB::Errors::DefineShareFailed

Exporting an SMB share failed! Details about the failure are

Error message

Exporting an SMB share failed! Details about the failure are shown
below. Please inspect the error message and correct any problems.

Host path: %{host}

Stderr: %{stderr}

Stdout: %{stdout}

What it means

SyncedFolderSMB::Errors::DefineShareFailed raised at plugins/hosts/windows/cap/smb.rb:116 in smb_prepare. Shares are created in batches of 10 by invoking the elevated set_share.ps1 (`Vagrant::Util::PowerShell.execute(script_path, *s_shares, sudo: true)`) after a UAC warning; a non-zero exit raises with the failing host path extracted from stdout ("share path: " prefix stripped) plus stderr/stdout.

Source

Thrown at plugins/hosts/windows/cap/smb.rb:116

            shares << [
              "\"#{hostpath.gsub("/", "\\")}\"",
              name,
              data[:smb_id]
            ]
          end
          if !shares.empty?
            uac_notified = false
            shares.each_slice(10) do |s_shares|
              if !uac_notified
                machine.env.ui.warn("\n" + I18n.t("vagrant_sf_smb.uac.create_warning") + "\n")
                uac_notified = true
                sleep(UAC_PROMPT_WAIT)
              end
              result = Vagrant::Util::PowerShell.execute(script_path, *s_shares, sudo: true)
              if result.exit_code != 0
                share_path = result.stdout.to_s.sub("share path: ", "")
                raise SyncedFolderSMB::Errors::DefineShareFailed,
                  host: share_path,
                  stderr: result.stderr,
                  stdout: result.stdout
              end
            end
          end
        end

        # Generate a list of existing local smb shares
        #
        # @return [Hash]
        def self.existing_shares
          shares = get_smbshares || get_netshares
          if shares.nil?
            raise SyncedFolderSMB::Errors::SMBListFailed
          end
          @@logger.debug("local share listing: #{shares}")
          shares

View on GitHub (pinned to 35f3160f4a)

Solutions

1. Read Stderr — the underlying New-SmbShare/`net share` failure is printed there
2. Ensure the host path exists locally and your account may share it
3. Accept the UAC prompt, or run vagrant from an already-elevated shell
4. Start the Server service (`net start lanmanserver`) and `vagrant reload`

# Every SMB host path must exist locally before vagrant creates shares
["C:/path/to/share"].each do |p|
  abort "SMB host path missing: #{p}" unless File.directory?(p)
end
# and the Server service must run:
system("net start lanmanserver >/dev/null 2>&1") || abort "Start the Server service"

begin
  env.machine_action(:up)
rescue VagrantPlugins::SyncedFolderSMB::Errors::DefineShareFailed => e
  puts "share creation failed for #{e.data[:host]}:\n#{e.data[:stderr]}"
  # verify path/elevation, start lanmanserver, then retry
  raise
end

When it happens

Trigger: `vagrant up`/`reload` with SMB folders on Windows where share creation fails: UAC elevation declined during the wait, host path invalid or inaccessible, Windows share-count/ACL limits hit, or the LanmanServer service stopped.

Common situations: UAC prompt dismissed or timing out; host_path on a nonexistent drive or a not-yet-mounted network path; group policy/AV blocking share creation; Server service disabled on tuned machines.

Related errors

• Pruning an SMB share failed! Details about the failure are s
• Vagrant is unable to setup a requested SMB share. An SMB sha
• Vagrant attempted to execute the capability '%{cap}' on the
• Vagrant requires administrator access to create SMB shares a
• The synced folder type '%{type}' is reporting as unusable fo

AI-assisted analysis of hashicorp/vagrant@35f3160f4a (2026-08-21). Data as JSON: /api/errors/98666d62940077b1. Report an issue: GitHub.