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Registry - ClassGUID

By mharkansas ·
Does anyone ever delete CLASS-GUID keys? Microsoft says not to mess with them.

I am trying to get rid of an iolo popup on the Windows Security Alerts on the system tray. I uninstalled System Mechanic (iolo) a year ago but this popup that the iolo antivirus is turned off keeps popping up. I have cleaned out all registry items mentioning iolo except three that it will not let me delete. They all relate to the same ClassGUID key.

These are the three it won?t let me delete at HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Enum\Root

LEGACY_IOLO_SERV (Legacy Driver ? iolo System Guard)
LEGACY_IOLO_SERV (Legacy Driver ? iolo DMV Service)
LEGACY_XPACKET (Legacy Driver ? iolo Personal Firewall Driver)

For example, this is everything in the registry on XPACKET:
(Default) REG_SZ (value not set)
NextInstance REG_DWORD 0x00000001 (1)


Default REG_SZ (value not set)
Capabilities REG_DWORD 0x00000000 (0)
Class REG_SZ Legacy Driver
ClassGUID REG_SZ {8ECC055D-047F-11D1-A537-0000F8753ED1}
ConfigFlags REG_DWORD 0x00000000 (0)
DeviceDesc REG_SZ iolo Personal Firewall Driver
Driver REG_SZ {8ECC055D-047F-11D1-A537-0000F8753ED1}-/040
Legacy REG_SZ 0x00000001 (1)
Service REG_SZ XPacket

Then you go to: Go to HKLM\SYSTEM\CurrentControlSet\Control\Class\{8ECC055D-047F-11D1-A537-0000F8753ED1}

Default REG_SZ Non-Plug and Play Drivers
Class REG_SZ Legacy Driver
EnumPropPages32 REG_SZ SysSetup.dll LegacyDriverPropPageProvider
Icon REG_SZ -19
NoDisplayClass REG_SZ 1
NoInstallClass REG_SZ 1
SilentInstall REG_SZ 1

And under that:
(Default) REG_SZ (value not set) they all have this
all the way to

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All Answers

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You have been Warned. :) :)


The {Class-GUID} subkey represents the component associated with the class-GUID.

Each {Class-GUID} subkey in the Class subkey represents a device class and is named by the GUID for the class. It appears as a 16-digit alphanumeric string within curly braces. These {Class-GUID} subkeys store configuration data that applies to the entire class of devices, such as the class of all modems.

Within the {Class-GUID} subkeys are 4-digit numbered subkeys, which represent particular devices that are instances of the class. These subkeys store data that apply only to that device.

Because the Class subkey is hardware specific, its contents vary widely. The Class subkey on your computer might look quite different from the attributes described in this reference.
Change Method

It is strongly recommended that you do not make changes to entries in the Class subkey or any subkey within it.


* The {Class-GUID} subkey is a variable representing the subkeys in the HKLM\SYSTEM\CurrentControlSet\Control\Class subkey. It does not actually appear in the registry. This variable subkey displays the entries and subkeys that are common to many of the subkeys in the Class subkey. The actual Class subkeys in your registry depend on the hardware installed on the computer or available to the system.


* To determine the type of hardware device represented by a {Class-GUID} subkey, use the registry editor Regedit.exe. Click the name of the class-GUID subkey (it appears as a 16-byte alphanumeric string within brackets). The device type appears in the value of the first, unnamed entry in the subkey.


* Do not change any entries in the Class subkey or any subkey within it. These subkeys are configured by the system to comply with Plug and Play standards. Changing any data can prevent your computer devices from starting or operating properly.

Please post back if you have any more problems or questions.

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Have you tried this

by Jacky Howe In reply to Registry - ClassGUID

Download and install CCleaner to tidy up your Registry. Backup the Registry as you go along, rescan again and again saving as you go until there are no errors left.
Cleaner: Windows
When you first open Ccleaner you will have an option to Analyze or Run Cleaner, after checking the left Pane and making your choices. Delete all Temp Files. If you scroll down you will see a greyed out box that has Advanced next to it. Left click on it and keep pressing OK to all of the responses. I normally Untick Windows Log Files and Memory Dumps as they may come in handy.
You don't have to install all of the add ons or shortcuts just the one to the Desktop.
See how you go with this and let us know how you get on.

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