I don't use System Mechanic, so I don't know how it installs hidden services and processes in the background, but what I would try is uninstalling in Safe Mode. Here's why;
Safe Mode is where the Windows Operating System is loaded up with only minimum drivers, services and processes. If you have never seen Safe Mode before it is as if only basic video has been installed, the Desktop display is black, and all icons are larger and less defined. This is what it looks like;
Safe Mode is a troubleshooting mode and is useful for sorting out problems, and in this case, if System Mechanic does not load up in Safe Mode, you can then remove it normally using the Control Panel's Add/Remove programs utility. Then, still in Safe Mode, you can goto MSCONFIG, (Start > Run, type in msconfig, click OK), and under the Startup tab remove any entries for System Mechanic. This stops any broken SM startup links from creating an error message.
Then reboot back into Normal Mode and SM should be removed.
The only problem I see is if SM also loads components when the OS is booted up into Safe Mode. To check that, whilst in Safe Mode, open the Task Manager, (right click the Taskbar, select Task Manager), click the Processes tab, scroll down looking for any SM entries, and end each task you find.
How to start Windows in Safe Mode.
I hope that helps.
I'd been using System Mechanic 7 on a Dell Dimension 4600 Windows XP for more than a year and downloading updates up to 7.5 when something happened (installation of conflicting software? I'm not sure) to make the icon in the Windows system tray at bottom disappear, so I can't access SM that way, nor can I get into it by clicking on the desktop icon -- I get error messages such as "Resource HP_TOOLBAR_BACKGROUND_RIGHT not found" and "Access violation at address 134E74C8 in module 'SysMech7.exe" The program continues to work well enough, but I can't get further updates, nor can I get into the program to change any settings. The thing is now like a runaway train that I can't control. The Iolo tech support is not very helpful. Their web help menu advises in its uninstall instructions that first one should close the Popup Blocker, System Guard, System Health, etc. as well as any scheduled maintenance programs by right-clicking their corresponding icons in the Windows system tray before uninstalling it with the Add/Remove Program in the Windows Control panel. Since the SM icon in the system tray has gone missing, I can't of course do those things. My question is, do I risk damaging my operating system if I just go ahead and use Add/Remove anyway? I'm also wary about having to go into the Registry to delete all traces of the program, since I know the danger of doing that if, like me, you're not a tech geek.
I've read some users' reviews of SysMech on cnet and it seems to have a bad rep. After I get rid of it, does anyone have a recommendation for a better utilities program that does the same kinds of functions that SysMech performs, but without its peculiar problems, and also has good responsive tech support?