SMB unix_err:'6e' error: 'Connection timed out'

Hi,
I’m trying to get my new raspi2 working and get those SMB errors.
My server is a windows server 2012 r2 with kodi and mysql. I want to share the database with other kodi installations in my lan (windows domain).
I can see the database contents (music albums etc.) on the osmc ui (connection to the mysql database is working) but I can’t access the files (mp3 etc).
Here are some configurations from my raspi:

osmc@raspi-an:~/.kodi/userdata$ cat advancedsettings.xml
<advancedsettings>
    <videodatabase>
        <type>mysql</type>
        <host>192.168.0.11</host>
        <port>3306</port>
        <user>xbmc</user>
        <pass>xbmc</pass>
    </videodatabase>
    <musicdatabase>
        <type>mysql</type>
        <host>192.168.0.11</host>
        <port>3306</port>
        <user>xbmc</user>
        <pass>xbmc</pass>
    </musicdatabase>
</advancedsettings>

osmc@raspi-an:~/.kodi/userdata$ cat sources.xml
<sources>
  <programs>
   <default pathversion="1" />
  </programs>
  <video>
    <default pathversion="1" />
  </video>
  <music>
  <default pathversion="1">Musik@Server1</default>
    <source>
      <name>Musik@Server1</name>
      <path pathversion="1">smb://192.168.0.11/musik/</path>
      <allowsharing>true</allowsharing>
    </source>
  </music>
  <pictures>
    <default pathversion="1" />
  </pictures>
  <files>
    <default pathversion="1" />
  </files>
</sources>

osmc@raspi-an:~/.kodi/userdata$ cat passwords.xml
<passwords>
    <path>
        <from pathversion="1">smb://192.168.0.11/musik</from>
        <to pathversion="1">smb://mydomain%5cmyuser:mypwd@192.168.0.11/musik/</to>
    </path>
</passwords>

Passwords.xml and sources.xml are created manually after reading a lot of posts about smb problems.
Kodi.log looks like this:

...
14:44:30 T:1957416960  NOTICE: Log level changed to "LOG_LEVEL_DEBUG_FREEMEM"
14:44:30 T:1957416960  NOTICE: CMediaSourceSettings: loading media sources from special://masterprofile/sources.xml
14:44:30 T:1957416960   DEBUG: CMediaSourceSettings:    Setting <default> source to : Musik@Server1
14:44:30 T:1957416960  NOTICE: Loading player core factory settings from special://xbmc/system/playercorefactory.xml.
...
14:44:39 T:1788617760 WARNING: Process directory 'smb://192.168.0.11/musik/' does not exist - skipping scan.
14:44:39 T:1576543264   ERROR: SMBDirectory->GetDirectory: Unable to open directory : 'smb://USERNAME:PASSWORD@192.168.0.11/musik'
                                            unix_err:'6e' error : 'Connection timed out'
14:44:39 T:1576543264   ERROR: GetDirectory - Error getting smb://192.168.0.11/musik/
...

In one of the threads I’ve seen a log message about “reading passwords.xml”, my log doesn’t include such a message is this one of my problems?
Can anybody help me out of this SMB hell?
Regards
Andreas