After upgrading to Mac OS X Mavericks (10.9) you may see many messages like this in your System Log (Console.app > System Log):
03/01/2014 10:46:00.554 secd: securityd_xpc_dictionary_handler Blotter copy_matching The operation couldn’t be completed. (OSStatus error -34018 - client has neither application-identifier nor keychain-access-groups entitlements)
03/01/2014 10:46:00.554 Blotter: SecOSStatusWith error:[-34018] The operation couldn’t be completed. (OSStatus error -34018 - Remote error : The operation couldn‚Äôt be completed. (OSStatus error -34018 - client has neither application-identifier nor keychain-access-groups entitlements))
This is a known problem with Mac OS X Mavericks that affects many sandboxed apps (any app sold on the Mac App Store) using calendar functionality.
We raised the issue with Apple when Mavericks was still in Developer Preview.
Apple is aware of the issue and they are working on a fix. In general Apple does not make promises about specific timelines for bug fixes but we are hopeful this issue will be fixed by the forthcoming Mac OS X 10.9.2 update.
In the meantime, please note that these messages do not indicate any real error in Blotter and the app should continue to function normally.