The Kunena team has announce the arrival of Kunena 7.0.4 [K 7.0.4] in stable which is now available for download as a native Joomla extension for J! 5.4.x/6.0.x. This version addresses most of the issues that were discovered in K 6.2 / K 6.3 / K 6.4 and issues discovered during the last development stages of K 7.0
Question
Installation error: -1 - An error has occurred. -It was not possible to copy the selected file.
I don't buy the "it's a permission's" explanation.
I've chmod'd all directories under webroot to 777 and all files within the different Kunena file space to 777 and it still does not work.
Regardless, it's a bad security practice to set directory and file permissions to 777. We're just asking for trouble down the road.
Fwiw I haven't discovered any problems from the aborted installation yet but as one of the previous posters predicted there's most likely bad consequences down the road.