If it's a flash drive it's likely infected with whatever crud is on the PC already. One place I worked had a world of problems due to a couple of flash drives that were infected and every time they were used (on an autorun enabled computer) they would infect another system. When they finally tracked those flash drives down they had some viruses on them.
Exactly, which is why I was attempting to determine if the installation media could be a possible source of his issues.
Sort of a domestic variation on the STUXNET worm/rootkit.
The installation media could even be a bootleg DVD image with all sorts of backdoors open or rootkit for a repeat performance.
Often, replacing files is only a short term fix, tracking down the source of the infection(s) is the tricky part.
@ Saad_111
The moral of the story:
1. Never run a system without proper antivirus/antimalware software installed and
active in a high security mode.
2. Never run a system without a proper firewall implementation as well as, an active router/firewall at the WAN connection.
3. Always know the source of all storage media and fully scan before attempting to access any file on such media, regardless of the source's previous reputation.
4. Avoid all media, updates, upgrades, etc, received via mail/delivery service, unless specifically requested from the shipper.
5. Limit all downloads to reputable known sites, then only download all files to a secure sandbox where they can be fully scanned before accessing.
6. Always download all media images directly from the company's website, avoid at all costs, media images from third parties.
7. Regularly install available security updates for the OS and applications installed on your system.
BigDog