To disable automatic startup of Lync 2010 client you can use one of the options bellow:
1. Using Group Policy Object (GPO):
a. Obtain “communicator.adm/x” file from Lync 2010 ISO file (not Lync 2010 Exe file).
* The file should reside in the “support” folder.
b. Import the Adm/x file to a new Group Policy Object (GPO) and apply the relevant settings.
2. Using a Logon script:
Set a logon script to apply the following registry changes:
Object Name: AutoRunWhenLogonToWindows
Object Type: REG_DWORD
Object Value = 0