tlbimp error TI1027

I could not find a single source of information about this error, not even in Microsoft docs.
Here is a scenario I encountered that caused this error – took a lot of work to figure out the root cause.

• Have two COM projects A & B, both running tlbimp as a post-build event.
• in project A, add /asmversion:1.2.3.4 to the tlbimp command line – this is the root cause
• compile project A -> will generate A.dll and ALib.dll
• compile project B -> will generate B.dll, and will fail generating BLib.dll with error TI1027

There are two ways to solve this error:

• Option 1 – remove the /asmversion command-line parameter, if you can.
• Option 2 – add /reference:<path to ALib.dll> to the tlbimp command-line of project B.

I’m not really sure why Option 2 works, but it does… if you have an explanation feel free to comment!