**To change the qc user password, you would do the following:**

1) Change the password in your database. (After this, users cannot login existing QC projects or create projects any more due to incorrect password! But users can still log into QC Site Admin.)

2) Log into QC Site Admininstration, click 'DB Servers' tab, click 'Quality Center User Password' button, type the new password set in MS SQL server. 'Confirm Change QC User Password' window will pop up, click 'Yes', the change will be applied to all existing QC projects. (What does it do? QC will automatically modify the filed in dbid.xml file for each QC project. Also, QC will automatically modify the DBSERVERS table in 'qcsiteadmin_db' schema - the value of 'DB_ADMIN_PASSWORD' filed will be changed to a new encrypted value. For some reasons, if QC fails to make these changes, users must perform them manually.)

If we restart QC server machine now, we cannot log into any QC projects or QC Site Admin, an error message 'Invalid Server Response' will be given, so we have to do the next step.

3) Stop the Quality Center service.

4) Open any of the project's dbid.xml files from the project repository (default location C:ProgramDataHPALMRepositoryDOMAINPROJECT) and copy the encrypted password string from the DB_USER_PASS tag

4) Open the siteadmin.xml file located in the installation path (default location C:programdataHPALMwebappsqcbinWEB-INF). Change the DefaultUserPassword string to the one copied from the project dbid.xml file and save.

5) Start the Qualitty Center service again and log back in. You should be able to access both Site Admin and projects as normal.