Does this message from console log give a hint?
15.02.16 22:37:01,578 sandboxd[162]: ([1245]) com.apple.messag(1245) deny file-read-data ~Library/Messages/Archive/2016-02-15/Freelancer am 2016-02-15 um 22.16.42.ichat
I have the full read and write privileges...
15.02.16 22:37:16,558 QuickLookSatellite[1151]: [MessagesQLGenerator] Transcript rendering connection interrupted
15.02.16 22:37:16,558 QuickLookSatellite[1151]: [MessagesQLGenerator] Transcript rendering connection interrupted
15.02.16 22:37:16,558 QuickLookSatellite[1151]: [Warning] [MessagesQLGenerator] Preview not generated
15.02.16 22:37:16,558 QuickLookSatellite[1151]: [Warning] [MessagesQLGenerator] Preview not generated
15.02.16 22:42:04,501 Messages[1260]: schema version 9005
15.02.16 22:42:05,191 Messages[1260]: 22:42:05.190 WARNING: 140: This application, or a library it uses, is using the deprecated Carbon Component Manager for hosting...
15.02.16 22:44:59,737 Messages[1265]: schema version 9005
15.02.16 22:45:00,413 Messages[1265]: 22:45:00.413 WARNING: 140: This application, or a library it uses, is using the deprecated Carbon Component Manager for hosting...
15.02.16 22:45:45,562 Messages[1270]: schema version 9005
15.02.16 22:45:46,237 Messages[1270]: 22:45:46.237 WARNING: 140: This application, or a library it uses, is using the deprecated Carbon Component Manager for hosting ...
15.02.16 22:46:07,430 sandboxd[162]: ([1275]) com.apple.Addres(1275) deny network-outbound /private/var/run/mDNSResponder
15.02.16 22:46:08,514 com.apple.AddressBook.InternetAccountsBridge[1275]: dnssd_clientstub ConnectToServer: connect()-> No of tries: 2
15.02.16 22:46:08,520 sandboxd[162]: ([1275]) com.apple.Addres(1275) deny network-outbound /private/var/run/mDNSResponder
15.02.16 22:46:09,615 com.apple.AddressBook.InternetAccountsBridge[1275]: dnssd_clientstub ConnectToServer: connect()-> No of tries: 3
15.02.16 22:46:09,621 sandboxd[162]: ([1275]) com.apple.Addres(1275) deny network-outbound /private/var/run/mDNSResponder
15.02.16 22:46:10,618 com.apple.AddressBook.InternetAccountsBridge[1275]: dnssd_clientstub ConnectToServer: connect() failed path:/var/run/mDNSResponder Socket:4 Err:-1 Errno:1 Operation not permitted
15.02.16 22:46:10,621 com.apple.AddressBook.InternetAccountsBridge[1275]: dnssd_clientstub ConnectToServer: connect()-> No of tries: 1
15.02.16 22:46:10,625 sandboxd[162]: ([1275]) com.apple.Addres(1275) deny network-outbound /private/var/run/mDNSResponder
15.02.16 22:46:10,629 sandboxd[162]: ([1275]) com.apple.Addres(1275) deny network-outbound /private/var/run/mDNSResponder
15.02.16 22:46:11,718 com.apple.AddressBook.InternetAccountsBridge[1275]: dnssd_clientstub ConnectToServer: connect()-> No of tries: 2
15.02.16 22:46:11,724 sandboxd[162]: ([1275]) com.apple.Addres(1275) deny network-outbound /private/var/run/mDNSResponder
15.02.16 22:46:12,803 com.apple.AddressBook.InternetAccountsBridge[1275]: dnssd_clientstub ConnectToServer: connect()-> No of tries: 3
15.02.16 22:46:12,809 sandboxd[162]: ([1275]) com.apple.Addres(1275) deny network-outbound /private/var/run/mDNSResponder
15.02.16 22:46:13,813 com.apple.AddressBook.InternetAccountsBridge[1275]: dnssd_clientstub ConnectToServer: connect() failed path:/var/run/mDNSResponder Socket:4 Err:-1 Errno:1 Operation not permitted
15.02.16 22:46:13,819 sandboxd[162]: ([1275]) com.apple.Addres(1275) deny network-outbound /private/var/run/mDNSResponder
15.02.16 22:47:53,065 com.apple.messages.TranscriptRenderingService[1293]: SACShieldWindowShowing:925: ERROR: NULL response
15.02.16 22:47:53,464 com.apple.messages.TranscriptRenderingService[1293]: [Warning] [MessagesQLGenerator] Could not unarchive file at url file:~/Library/Messages/Archive/2016-02-15/Freelancer%20am%202016-02-15%20um%20 22.16.42.ichat
15.02.16 22:47:53,468 QuickLookSatellite[1151]: [Warning] [MessagesQLGenerator] Preview not generated