Can not login to DASH because of Invalid user id error.

Answer

Take a look into below files:

<DASH_HOME>/profile/config/cells/JazzSMNode01Cell/fileRegistry.xml
<DASH_HOME>/profileconfig/cells/JazzSMNode01Cell/security.xml

The security.xml file contains default admin user id used during the installation. See below sample snippet from security.xml file. In this case smadmin is the user id.

------------------ snippet from security.xml -----------------

<userRegistries xmi:type="security:WIMUserRegistry"
xmi:id="WIMUserRegistry_1" serverId="" serverPassword="{xor}"
realm="defaultWIMFileBasedRealm" ignoreCase="true"
useRegistryServerId="false" primaryAdminId="smadmin"
registryClassName="com.ibm.ws.wim.registry.WIMUserRegistry"/>
<authConfig xmi:id="AuthorizationConfig_1" useJACCProvider="false">

--------------------- end snippet ----------------------------------------------

See below snippet from the fileRegistry.xml file. In this case smadmin is the user id and password is enclosed in <wim:password> tags in encrypted format.

If you do not remember the password then replace password string in fileRegistry.xml with the following string, which is equivalent to tipadmin. Make a backup copy of fileRegistry.xml before making any changes.

U0hBLTE6eXNuYmdkb255eXY3OjBtbE55b2c2T3FXUVBOWGMvZlZlbkVkMW5EVT0K

-------- snippet from fileRegistry.xml -------------------------
<wim:Root>
<wim:entities xsi:type="wim:PersonAccount">
<wim:identifier externalId="3209475e-7723-4bdb-9926-dfd5e178cc0a"
externalName="uid=smadmin,o=defaultWIMFileBasedRealm"
uniqueId="3209475e-7723-4bdb-9926-dfd5e178cc0a"
uniqueName="uid=smadmin,o=defaultWIMFileBasedRealm"/>
<wim:parent>
<wim:identifier uniqueName="o=defaultWIMFileBasedRealm"/>
</wim:parent>
<wim:createTimestamp>2013-04-25T13:54:38.439-04:00</wim:createTimestamp>
<wim:password>U0hBLTE6dHY5emxidnlmaTNoOmpDWmkrRUNxZ29OcTZWa0I1dm5zVU5VSEpZMD0K</wim:password>
<wim:uid>smadmin</wim:uid>
<wim:cn>smadmin</wim:cn>
<wim:sn>smadmin</wim:sn>
</wim:entities>
</wim:Root>
--------------------- end snippet ---------------------------------------

If you wish to disable the security then follow steps in technote below. After that you should be able to login without password and correct any configuration issues which may be causing login issue.

https://www-304.ibm.com/support/docview.wss?uid=swg21499504

If above guidelines does not help then please open a PMR and provide logs as described in below technote for investigation.

https://www-304.ibm.com/support/docview.wss?uid=swg21470063

In addition provide below files:
<DASH_HOME>/profile/config/cells/JazzSMNode01Cell/fileRegistry.xml
<DASH_HOME>/profileconfig/cells/JazzSMNode01Cell/security.xml