explorer error

Need to know the specific error to provide an answer.

There are links to sites with error lists and suggested corrective action at www.bootdisk.com

Often, explorer errors arise from too many services trying to run at once, and Windows runs outof memory.

Also, over time, Windows "self-corrupts" that is you have program and file calls that are in error embedded in the registry.
Good PC maintenence is the best preventive action.
Properly uninstall programs.
Scandisk, and defrag at least once a month.
Clean out the Windows\temp and temporary internet files folders on a regular basis.

I use either Norton WinDoctor, or On-Track Fix-It to help keep my systems registries clean. Even then, they don't clear up every registry error.

Every 6 months to 2 years, it reaches the point, where the "best" way to repair Windows is to wipe the hard drive and start over again.

Chas