How to repair a crack in the foundation?

[Mjärn]

As the headline reads. How do you fix this crack?

 

[Plupp 405730]

Since you can't see what kind of masonry is behind or plaster, you should start by knocking down the cracked and loose parts and then take pictures when it is opened...

 

[Ossian K Olsson]

As the title says. How do you fix this crack?

The easiest way is to walk by, think "I should take care of that" and then continue doing so for the next 50 years.