The project i am working on all of a sudden is giving me "failed to copy source folder" when I try to export a apk file.

nothing too helpful to offer but i was able to export to (google) apk without issue using the latest version.
i also ran a google search of the forums and found 1 other thread referencing the error; it was for iOS (and i saw no follow-up) but it leads me to believe the issue might be with a failure to copy the android player into the export.

i'm assuming you're using the latest version and tier 1?

otherwise, sorry i couldnt be more help :/

add: fixed the typo in thread title ("sorce") for future reference/in case we figure out what the issue is

Last resort I uninstalled then reinstalled low and behold the problem went away. Thanks for the reply Virtual Nomad

Dennis W