[HELP] This warning appears every time I boot my PC (.dat)

[jsxruu]

OS:Windows7 U
version:6.0.1091

Every time I boot my PC,one warning link following appears,report a file named *.dat.

[Lisandro]

I suggest:

1. Clean your temporary files.
2. Schedule a boot time scanning with avast with archive scanning turned on. If avast does not detect it, you can try DrWeb CureIT! instead.
3. Use MBAM (or SUPERantispyware or even Spyware Terminator) to scan for spywares and trojans. If any infection is detected, it is better and safer to send the infected file(s) to quarantine (Chest), rather than simply deleting them.
4. Test your machine with anti-rootkit applications. I suggest avast! antirootkit or Trend Micro RootkitBuster.
5. Read this instructions and provide more info with the logs generated.
6. Clean your Hosts file (replacing it) with HostsMan tool.
7. Disable System Restore and then reenable it again.
8. Immunize your system with SpywareBlaster.
9. Check if you have insecure applications with Secunia Software Inspector.

[DavidCo]

Please find the file (search)
Where is it located (folder)
What size is it

[jsxruu]

Please find the file (search)
Where is it located (folder)
What size is it

location:    C:\ProgramData\AVAST Software\Avast\arpot (see it in image)
size: several,less than 100 KB