I have trie dto install Lync 14.0.9. It crashes on startup. I have removed and installed multiple times including going through the steps of removing keychain, plist etc. Nothing works. Its being a year now 14.0.7/8/9 all crashing on Mac. I think I need to ask my company to stop using this as this is causing so much waste of time

Microsoft Error Reporting log version: 2.0

Error Signature:
Exception: EXC_BAD_ACCESS
Date/Time: 2014-10-07 15:47:15 +0000
Application Name: Microsoft Lync
Application Bundle ID: com.microsoft.Lync
Application Signature: UCCP
Application Version: 14.0.2.120223
Crashed Module Name: libcorecrypto.dylib
Crashed Module Version: unknown
Crashed Module Offset: 0x000278c8
Blame Module Name: Microsoft Lync
Blame Module Version: 14.0.2.120223
Blame Module Offset: 0x002c05c6
Application LCID: 1033
Extra app info: Reg=English Loc=0x0409
Crashed thread: 0

The problem is version of the Dylib files 

 libcorecrypto.dylib

Application Version: 14.0.2.120223

Before you install the Lync for Mac 2011 14.0.9 update, you must uninstall any version of Lync for Mac 2011 that is earlier than Lync for Mac 2011 14.0.4 from your computer. Additionally, make sure that the computer is running Mac OS X 10.5 or a later version of the Mac OS X operating system.

Please uninstall The lync for MAC client and install 

https://support2.microsoft.com/kb/2963369

Hi,

I recommend to do the steps Edwin provided above.

When you uninstall Lync for Mac 2011, you can refer to the link below to uninstall it completely:

http://technet.microsoft.com/en-us/library/jj945448(v=office.14).aspx

Then try to install the Hotfix KB2979062 for Lync for Mac 2010 14.0.9 to check if the issue again:

http://support2.microsoft.com/?kbid=2979062

Best Regards,

Eason Huang

Agree with Eason. Try to full uninstall (http://technet.microsoft.com/en-us/library/jj945448(v=office.14).aspx) and this time rebooted before attempting another install. Then start to install it again.