Error while installing VSTU (error cod 1603)

When installing UNIT, I had the following error
Unity 5.2.1f1 Download Assistant
Error while installing VSTU (error cod 1603)

I have the button chosen ignore
The installation is made. UNITY has the air to operate normally
But what can be the consequences of this error?
Kind regards

The error is from Visual Studio Tools for Unity and I guess it comes from the fact that you already have VSTU installed, so you can ignore it and it will skip the VSTU installation. I got the same error, I choose ignore and everything seems to work just fine.