When using PLMSynchro (Online Mode) with Creo/Windchill you will run into problems with the login. Windchill does not allow autologin and will always force a dialog. (Up to now solved by scripting < V12 SP4).

In order to perform an automatic login to Windchill, now use following setting:

PdmProxies.cfg:

[PdmProxyTranslator]
#:HELP; Callback that is executed after a CAD instance has been started. 
 Use this to perform a PDM login or similar tasks.
#       Available objects:
#         <cadSr>       The scripting root (cadScriptingRootC)
#       Examples:
#         AfterCadStart=PdmProxyHelper.AfterCadStart(cadSr, "cnstools.creo7", 
 "http://devwindchill12/Windchill", ""user", "password", "WcServerAlias", "WcWorkspaceName")
#:VALS_S;
#:INACTIVE;AfterCadStart=

Example:

AfterCadStart=pdmProxyHelper.AfterCadStart(cadSr, application.resolveEnv("%CREO_APP_PRX_ID%"), 
 "http://DEVwindchill12.cadenas.internal/Windchill", 
 "Slayer", "Slayer", "WC12_TEST", "DELVE_TEST")