This is often caused by malware damage, and malware can hide in the System Restore backup files where it can remain undetected by anti-virus and anti-spyware scans.
I would disable System Restore, which deletes all restore point backup files, the re-enable it again. Right click your My Computer icon, select Properties, then in the System Restore tab, disable System Restore, click Apply. Then re-enable.
You may want to update and scan with your anti-malware utilities in-between disabling and enabling, in Safe Mode, where most malware cannot load up.
Also, I would consider scanning with MalwareBytes AntiMalware, (MBAM), from http://www.malwarebytes.org/.
I note you use a downloader, so you put your system at greater risk from infected files, even if the P2P based application is spyware and adware free itself.
Also, I note you use a system optimizer. I have never used IObits Advanced System Care myself, but I tend to stay away from such utilities because one wrong delete and they can do more damage than they help.
I don't know about the printer problem, but perhaps you could disconnect the printer, uninstall the software, reboot, re-install the software before connecting the printer again. See if that resolves it.
Mark
I have a pentium IV desktop computer with D101GGC motherboard with 2gb ram and two hard drives, one sata
(seagate) and another, pata (samsung) with a total capacity of 160GB. operating on win xp prof.sp3.
The system is protected by avast antivirus and zone alarm firewall. I use IObits Advanced system care and ccleaner
to maintain the computer. My downloader is Orbit downloader.
I have the following problems.
1. For the past one week, the printer drivers get uninstalled without any warning.
2. I normally create restore point after a thorough cleaning of registries, junk files using the above mentioned
softwares. When I wanted to restore to an earlier restore point using system restore, it informs that it could not be
restored and there is no changes made to the system. I tried another system restore point. Both returned with a
message that the system restore could not be done.
These led me reinstall the drivers. I am more worried for system restore not restoring to an earlier restore point. I
had tried two system restore points. Both returned not restoring the restore points.
I will be thankful if some expert guide me as to what could be reasons for not restoring and how to remedy the
situation of restoring the system to earlier restore points.
pscraja.

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