Symptoms of vSphere 5.5 Single Sign-On [email protected] password issues are listed below:

• Cannot register the vSphere Web Client with a different vCenter Single Sign-On (SSO) instance.
• Cannot register VMware vRealize Automation 6.x (formerly known as VMware vCloud Automation Center) with vCenter Single Sign-On instance.
• Cannot register vCenter Server Heartbeat with incorrect password.
• Registering the vSphere Web Client with a different SSO instance fails.
• When running the client-repoint.bat command, you see the error:
  
  Error registering vSphere Web Client with VMware Lookup Service
  
  Note: For more information, see Re-pointing and re-registering VMware vCenter Server 5.1 / 5,5 and components (2033620).
• In the vCACConfigurtion- date _Kopie.log file, you see entries similar to:
  
  Info : 2014-01-31 02 02 29 759 PM : System.Net.WebException: Couldn't create SOAP message due to exception: [com.ctc.wstx.exc.WstxLazyException] com.ctc.wstx.exc.WstxUnexpectedCharException: Unexpected character '<' (code 60); expected a semi-colon after the reference for entity '** replaced, part of customer PWD‘
  Info : 2014-01-31 02 02 29 759 PM : at [row,col {unknown-source}]: [10,32] ---> System.Net.WebException: The remote server returned an error: (500) Internal Server Error.
  
  
  Note: The preceding log excerpts are only examples. Date, time, and environmental variables may vary depending on your environment.

• Non-ASCII characters
• Ampersand (&)
• Semicolon ( ; )
• Double quotation mark ( " )
• Single quotation mark ( ' )
• Circumflex ( ^ )
• Backslash ( \ )
• Percentage (%)
• Angle brackets ( < , > )

For more information, see Installing vCenter Single Sign-On 5.5 fails if the password for [email protected] contains certain special character (2060746) .

• Special characters such as ($) and (@) work when used in the SSO password.
• Using an exclamation character (!) in the SSO password for the [email protected] user when installing SSO is valid. The SSO installation succeeds, but re-pointing the vSphere Web Client to a different SSO instance fails in vCenter Server installations prior to vCenter Server Update 2.
• For more information on re-pointing the vSphere Web Client to a different SSO instance, see Re-pointing and re-registering VMware vCenter Server 5.1 / 5,5 and components (2033620).

For more information, see Troubleshooting special character issues in vCenter Server 5.5 (2061415). 

For more information, see the Configuring vCenter Single Sign-On section in the vSphere 5.1 Security Guide.