Subassemblies in SPH won't attach

[RocketBlam]

I created a subassembly from two fuel tanks, a jet engine and an intake, intended to be placed radially. When I select it, it won't connect to the ship even though it is green, and I can never thereafter get the thing off my cursor. I can't "throw it away" in the area to the left as you normally can. It is stuck to the cursor and the only way to continue is to quit out of the SPH.

This same part behaves the same way in the VAB.

Another, similar part (radially attached) does the same thing.

ETA: Subassemblies designed for in-line attachment work fine.

The only installed mod is MechJeb.

Edited May 4, 2015 by RocketBlam

[SurlyAardvark]

I was having the same issue... I think it is caused by some sort of file corruption, because verifying my game cache fixed the problem.

To verify cache:

Right click Kerbal Space Program -> Properties -> Local Files -> Verify Integrity of Game Cache

[ExplorerKlatt]

I was having the same issue... I think it is caused by some sort of file corruption, because verifying my game cache fixed the problem.

To verify cache:

Right click Kerbal Space Program -> Properties -> Local Files -> Verify Integrity of Game Cache

That is assuming the OP uses Steam.