Check if a particular program is slowing the machine when you switch on, e.g. an antivirus program, go to Control Panel > All Control Panel Items > Performance Information and Tools > Advanced Tools (in the left pane). The problem is sometimes shown on this screen, although you may have to click Advanced tools in the left pane then View performance details in the Event log.

If the problem isn’t shown, click the Windows Orb (Start) > All Programs > Accessories, right-click Command Prompt then ‘Run as Administrator’. Copy and paste or type wevtutil qe Microsoft-Windows-Diagnostics-Performance/Operational /f:text > %userprofile%\Desktop\Event.txt (note the five spaces) and press Enter. If you Copy and Paste the command, use mouse right-click to paste it into the prompt. Close the Command Prompt and double-click Event.txt on the Desktop to open it. Go to the end of the file (Ctrl+End) to see the most recent events. Those with an Event ID in the 100 series are start up events and there may be a name or reason in the event listing.

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