A computer-implemented method, and computer program product, for switching the I/O protocol of a multiprotocol I/O adapter while a computer system including the multiprotocol I/O adapter is running. The method comprises running a multiprotocol I/O adapter using a first I/O protocol while a computer system including the multiprotocol I/O adapter is running, and logically removing the adapter from the system while the computer system continues running. The multiprotocol I/O adapter is then caused to switch to a second I/O protocol while the adapter is logically removed and the computer system continues running. While the computer system still continues to run, the multiprotocol I/O adapter is restarted. After restarting, the multiprotocol I/O adapter runs using the second I/O protocol while the computer system continues running. In a virtualization environment, the method allows a multiprotocol I/O adapter to meet the varying I/O requirements of one or more virtual machines.