Cannot view the job log (java.io.IOException)

hello,

I cannot view serveral job log in the Data Service Management Console.

In the Trace Job Log, there is an error "java.io.IOException".

But I can view the another log with the same Repository and job server.

The Trace file and the Monitor file of the job log are both in the directory D:\localapp\apps\SAP BusinessObjects\Data Services\log\JobServer_1\....

Thanks for your help

Xin