This is just a generic error message - there is no "other person"

If you Disable the Performance Logs and Alerts service then you might be able to delete the file(s).

smlogsvc.exe = Performance Logs and Alerts Service

Programs such as EasyCleaner can create Perflib_Perfdataxxx.dat files. These files do no harm and can be left on the hard drive.

Here's more than you may want to know.

Perflib stands for Performance Library. Perfdata stands for Performance
Data.

The %SystemRoot%\System32\Perflib_Perfdataxxx.dat files are created by the
System Monitor. And/or
%userprofile%\Local Settings\Temp\Perflib_Perfdataxxx.dat.
or
C:\Documents and Settings\Your Name Here\Local
Settings\Temp\Perflib_Perfdataxxx.dat. When you shutdown normally, the file
should be deleted.

If you have an abormal shutdown, these files can become orphaned, and
accumulate on your computer.

Under some yet to be determined circumstances, these files can become
orphaned during normal operation.

The Windows Performance tool is composed of two parts: System Monitor and
Performance Logs and Alerts. With System Monitor, you can collect and view
real-time data about memory, disk, processor, network, and other activity in
graph, histogram, or report form.

To open Performance...
Start | Run | Type: perfmon.msc | Click OK

You can view this by opening the Task Manager. The Performance tab displays
a dynamic overview of your computer's performance, such as CPU and various
kinds of memory usage.