Hi. I need to update my copy of X1 but I have noticed a problem in the update instructions PDF that's caused some confusion.
It says that Essential (my version) is build 184 where as my about popup says its 185 (the PDF says this is studio. 
What version of the updates should I install? for essential or studio?
 
 

The updates are here http://www.cakewalk.com/Support/By-Product/SONAR%20X1
The X1c Essential update can update any prior version of X1 Essential, then apply X1d Essential update. You can only apply updates to a like version. IOW X1 Essential can only be updated by X1 Essenial updates. X1 Studio can only be updated with X1 Studio updates. X1 Essential cannot use X1 Studio updates.
 
While the build number is important, more useful is the designation before the build number. Usually in the SONAR about screen, to the left of the build number is the release designation, for example X1, X1a, X1b.... This lets you know which updates may be need.

Yeah. I have some updates downloaded (C and D) there are none prior to those.  The issue I had was build numbers being confusing. There were no letters before.  just (build 185)I'll just install best guess and if it goes wrong do a repair install.

Hmm. Oddly, X1 Essential does not show the release(a,b,c).
However, X1d Essential is build 185, so you are as updated as X1 Essential got.
Is there a particular issue that you are trying to resolve?