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CRM 2011 - up to date (rollup 6) - suddenly we can't make double-book a user.
So, in all our organizations, even ones without any customizations, if a user double-books themselves (creates an appointment for a time where an appointment already exists) CRM creates a popup that gives the user the option to "Cancel" or "Ignore and Save". If the user chooses to "Ignore and Save" the popup closes but then the original screen goes blank and reports "Access Denied / This form is no longer available. As a security precaution, Microsoft Dynamics CRM does not automatically resubmit your information for you. To continue, close and reopen the form, enter your information, and then save the form."
The trace file reported "System.Web.HttpUnhandledException: Microsoft Dynamics CRM has experienced an error. Reference number for administrators or support: #83038804: System.Web.HttpUnhandledException (0x80004005): Exception of type 'System.Web.HttpUnhandledException' was thrown. ---> Microsoft.Crm.CrmException: INVALID_WRPC_TOKEN: Validate WRPC Token: WRPCTokenState=Invalid, TOKEN_EXPIRY=4320, IGNORE_TOKEN=False, TOKEN_KEY=j5kqkV7/EeG+8gAeC8HuqS0B4graTXKddKbe2LWU6wpHP3L6bU6ycbk9pKjuRCV4"
You might try the work around listed here:
There is a hotfix available for this problem. Please contact Dynamics CRM Support and request the hotfix. I would not suggest that you disable WRPC token validation.
I'm getting the same problem with UR11 applied. Does this hotfix applies?