I did the registry cleanup, and and still can't download Avast :
17.04.2008 06:02:18 general: Started: 17.04.2008, 06:02:18
17.04.2008 06:02:18 general: Running setup_av_pro-491 (1169)
17.04.2008 06:02:18 system: Operating system: WindowsXP ver 5.1, build 2600, sp 2.0 [Service Pack 2]
17.04.2008 06:02:18 system: Memory: 72% load. Phys:64032/228708K free, Page:299740/559692K free, Virt:2069600/2097024K free
17.04.2008 06:02:18 system: Computer WinName: YVONNE
17.04.2008 06:02:18 system: Windows Net User: YVONNE\YRyan
17.04.2008 06:02:18 general: Cmdline: /sfx /sfxstorage "C:\DOCUME~1\YRyan\LOCALS~1\Temp\_av_sfx.tm~a02312" /srcpath "C:\DOCUME~1\YRyan\LOCALS~1\TEMPOR~1\Content.IE5\A17ST03E"
17.04.2008 06:02:18 general: DldSrc set to sfx
17.04.2008 06:02:18 general: Old version: ffffffff (-1)
17.04.2008 06:02:18 general: Install check: SetupVersion does NOT exist
17.04.2008 06:02:18 general: SGW32P::CheckIfInstalled set m_bAlreadyInstalled to 0
17.04.2008 06:02:18 registry: ERROR!:Cannot access registry HKLM\SYSTEM\CurrentControlSet\Services\avastTestService, error code: 0x000005AA
17.04.2008 06:02:18 general: Err:Not enough user rights to continue