Within Assemblies, does the "unbuild" function require the BOM add-on module? I do have "Allow negative Inventory" enabled. After entering "-1" for quantity I see the "Build" button switch to "Unbuild" yet I am notified that the integer must be positive.

Thank you.

Unbuild requires the BOM add-on.

Not sure why you are getting this error. What versions of OE, IC, & BOM are you using? Is BOM licensed or has it expired?

Thank you. I was starting to suspect that was the case.

I had the same error and then found out I required the BOM add-on. For the hundred and fifty or so unbuilds/builds I do a year, the add-on wasn't worth the cost.