Can I save the Hanar homeworld?

At the end of the quest "Citadel: Hanar Diplomat" the indoctrinated Hanar manages to upload a virus that disables the defense system of the Hanar homeworld. The salarian Spectre with me tried to stop it but was attacked by the human nearby and failed to prevent the virus upload.

Is there any way for me to stop the virus upload and save the Hanar homeworld?

Solution 1:

If you have imported a saved game from Mass Effect 2 in which you completed the Kasumi - Stolen Memory DLC and also had her survive the assault on the collector base, she will cloak herself and follow you around for the duration of this mission. At the end, you'll automatically help save the Salarian while she stops the upload.

Based on your own answer, it sounds like if you do not have Kasumi with you, you have to choose between saving the Salarian and stopping the upload. If Kasumi is with you, both are successful.

As an added bonus, not only have you saved Jondum Bau and saved the Hanar homeworld, but Kasumi herself will count as a 25 point war asset.

Solution 2:

Replaying the scene I found that actually the Renegade interrupt I acted on was to blame. I did act so quickly on it that it cut off the part of the conversation that explained that I should prevent the upload myself and not help the Salarian. By not acting on the Renegade interrupt I saved the Hanar homeworld, but lost the help of the Salarian Spectre.

It's not exactly intuitive in this case, as I wouldn't think of saving one person on the cost of an entire world a Renegade action.