R3 - Default URLSearchHook is missing

O2 - BHO: Router Layer - {5EB7CB50-E375-4718-B4C0-9AD12EFA2F84} - C:\WINDOWS\System32\aclayer.dll (file missing)

O2 - BHO: Infofo 工具栏 - {D74EC18E-3DDD-4174-B1B1-949FE3B8366D} - C:\Program Files\Infofo Bar\infofobar.dll (file missing)

O3 - Toolbar: Infofo 工具栏 - {D74EC18E-3DDD-4174-B1B1-949FE3B8366D} - C:\Program Files\Infofo Bar\infofobar.dll (file missing)

请问怎么可以修复他们啊  这些文件坏了会影响到系统哪些方面啊!!!谢谢帮忙啊