I just encountered this problem, and my KBao also prompted that the file signature failed during installation. I went directly to the last "Install" in the line below the "Personal Online Banking Login" point on the website of the Agricultural Bank of China, clicked "Driver Install" after entering (at this time, K-Bao has plugged in the computer), and then downloaded an installation file from the website, and the installation was successful. I hope you are in the same situation.