I've seen several suggestions to repair this.  Some say to add cream cheese or more butter.  Does it have to be refrigerated then?   Thank you in advance.

I use butter in my ABC & don't refrigerate it but definitely do when using cream cheese. SMBC is a great alternative if you don't like super sweet ABC. 

Please be advised that buttercream icing is MEANT! to be sweet.  Are you adding a generous pinch of salt?  What recipe are you using?  What is sweet to me might be either not sweet enough or too sweet to you as everybody's tastes differ.  There are recipes out there that add cr ch to b'cream and do not need refrigeration.  Earlene Moore's recipe is one that I am familiar with.  Do a search on her name. 

The more butter (or any fat) used the less that b'cream will crust - some to the point of never crusting.  So don't just add more, replace the other fat you are using.  In other words if you recipe call for 2 cups of fat (shortening, Crisco etc) than reduce that by 1/2 cup adding 1/2 cup butter (rather that using 2 cups of fat *and* 1/2 cup of butter.)

Also try adding more and/or different flavoring.   

use buttermilk for the liquid

Thank you for your reply.  Yes, a little sweet, but not to the point of being sickening.  My Dad owned bakeries (the old fashioned kind) and you could eat his B/C right off a spoon.  It was delicious.  I see that a lot of  southerners seem to like really sweet B/C.  I wish I was able to spend more time in the back of our bakery rather than up front with the customers.  I was using Wiltons recipe, but did equal parts butter and Crisco.  Some B/C even feels grainy, or greasy.  Also Dad's never crusted so I guess he used more butter.

Wouldn't that make a big change in the taste?  And I'm sure it would have to be refrigerated?  I don't want to use anything that needs refrigeration (besides W/C.

what makes a big change in taste -- the buttermilk? naw -- it mellows it -- make a small portion of icing and try it -- it's really good --

i don't know maybe you meant something else? did you mean the bmilk?

yes, I meant the buttermilk.  OK, I'll try that someday.  Thanks for the tips ladies.

it adds the tartness of the cream cheese without the need to refrigerate -- seriously if you want a less sweet abc that's where you can get it