Microsoft Net Framework 3.5

[Deidre]

On Host Ubuntu 14.94, Virtualbox 4.3.10, I am running guest Windows 8.1 in order to run one single Windows-based application. All was honky dory as long as I only used an XP guest, but since XP is now considered a security risk, I bought a licence for Win 8. It turns out that the application I need (SDL Multiterm, as it happens) requires, and tries to download, Microsoft Net Framework 3.5. I get
an error message telling me I don't have access to internet. I try adding through control panel - which is, in theory, possible, but am again told I don't have access to Internet. But I do! To the extent I have tested the Windows guest, everything is working fine, USB, CD, Internet, sound. And Internet too. I did everything by the book (official Microsoft guidelines). Am I missing a setting somewhere?

Hope somebody can help me with this, because I really need that application.

[Deidre]

Very sorry, or rather very pleased, that the problem seems to have solved itself. I can't imagine how. I have been toying with it for a couple of hours. Turned off firewall more than an hour ago, but while I was writing the above question, the missing module quietly installed itself.

I made no changes to settings. All I did was turn off firewall and wait (!) even to the point of not waiting any more.