Ijust checked my computer for trojan horses, with Bit Defender, and we found 4 Trojan Horses, within the Avast Program Files : PWS.Onlinegames.KBNW. These files can neither get desinfected, nor moved or quarantaned. Could you please look into this ?
Schedule a boot time scanning with avast with archive scanning turned on. If avast does not detect it, you can try DrWeb CureIT! instead.
Use SUPERantispyware, MBAM or Spyware Terminator to scan for spywares and trojans. If any infection is detected, better and safer is send the file to Quarantine than to simple delete them.