My dishwasher works for few minutes and then shows E4.
It does not work for few days and if I try after a week or 2, it start to work but will stop in between by showing the same error E4.

faizi, August 2016

Late on I know but:

You could read the manual
You could search for the manual online, download that and read it.
You could do some simple Google searches, preferably including the model of your machine and the exact message it gives you.

Here's a manual I found. It may or may not be for your exact machine but read page 24, which may be enlightening

https://www.partmaster.co.uk/images/mediator/1552/Sandstrom%20SDW60B10%20IB.pdf

You may have water in the base that has activated a float switch. The short term solution is to mop the water out of the base and check the float switch is free to move. Longer term you need to check for - and cure if necessary - any leaks.

Acp, August 2017