When I switched on my PC all the shortcut icons had disappeared.  A message popped up about it being unable to connect to the E directory.  Restarting didn't help.

This could be many things.  If you have a blank screen or a plain blue one it can indicate that the PC has got stuck in a CPU loop which could be a hardware problem, or a disk misread while fetching software, or that Windows Explorer has failed to load or the boot process has failed before it has got to Windows Explorer.  If you have a basic desktop but are missing all or most of your shortcut icons then you could have a problem with the icon cache file.  The Icon Cache or IconCache.db is a special database file in which Windows keeps copies of each icon so it can get a copy quickly instead of retrieving the icon image from the original application file.

The message about drive E is not in itself indicative of a particular problem since it depends what drive E is used for, which will be different for different systems.  If you have multiple partitions on your internal hard drive these will be allocated consecutive letters starting from C.  The optical drive is allocated the next letter followed by attached USB drives. So E could be a partition of the internal hard drive, an optical drive or an attached USB drive.  The message could be caused because there is a file needed to complete the boot process on drive E which it can't access, (though this would be unusual unless you had tailored your system).  Or, in the case of USB attached drives which are checked during the boot process, that it is having trouble reading drive E.

Without specific text of error messages it is hard to be more precise.  Unless you have a hardware problem, in which case a specialist repairer will be needed, a reboot will normally get you over transient disk read errors. If you have rebooted already then you should do so again but use the power off button rather than a software restart link.  Before switching on, unplug all the USB attached drives, they can be plugged in, one at a time, after the boot has completed.

The most likely cause for symptoms like this is the Windows Update process.  This used to be under the control of the user, but with Windows 10 Microsoft decided to remove user control and make the process automatic ^[Note1].  In the process they have made a right mess of it.  Sometimes you get messages informing you of what is going on, sometimes the "restart" option on the start button is changed to "Update and restart", but these can not be relied upon.  The only things you can be sure of are:-

• Update will occur at the most inconvenient time
• The process will be long and painful
• The computer will not behave as normal until the update is complete

For these reasons it is recommended that you take controlof the update process, see the link in note 1.  There is nothing worse than losing your compputer to a three hour update when you are in a hurry.

During the update process you will see screens with (inaccurate) progress bars, but at other times the screen is blanked, or set to a single colour with no indication if anything is happening or not.  This is bad programming practice.  It seems to me that Microsoft employ coders straight from college who think they know everything but in reality have no experience.

One thing is sure, interrupting the update process with a reboot does not help.  Once your PC starts to update leave it to do it and go away and do something else.  You just need to check periodically that it is not waiting for you to enter your sign-on password, (this may be required more than once).  Sitting in front of the PC during this process, waiting to get on with what you urgently need to do, will only lead to frustration.

If you have determined that your icon cache is damaged you can repair it.  How you do this depends on which version of Windows you have.  You can find further guidance on these links, Windows 8/7, Windows 10.  These sites have adverts which should be avoided, they may be offering useful services but it is not worth risking that they are trying to scam you.

[Note1]: Users no longer get asked if they want to apply an update but you can still have some control over the update process in Settings, see 2005.htm.  (back).

13th March 2020.  Minor changes 15 December 2022

Addendum: November 2022

In this particular case the problem was that an internal hard drive connector had become loose.  This sort of problem, where the whole machine behaves differently rather than just one program has strange symptoms, can have many different causes which lead to similar looking symptoms and usually require hands on rather than remote diagnosis.