This counter tracks packets output by the crypto accelerators that were found to have errors, such as checksum errors or other faults, accumulated since the last reboot. A nonzero and climbing count here is a direct sign that the crypto hardware is producing corrupted output, which for something like IPsec would likely cause the receiving peer to silently drop those packets, showing up as unexplained packet loss on the tunnel rather than an obvious local error. If a specific VPN tunnel is losing a small, steady percentage of packets and this counter is climbing in step, the root cause is more likely the crypto hardware itself than the network path between the two endpoints.