What you want to ask is why imcore.dll's signature verification failed? The reasons are certificate problems and files being tampered with or damaged.

1. Certificate problem: Signature verification failed because the digital certificate used has expired, is invalid or has been revoked. Digital certificates are used to verify the authenticity and integrity of files. If there is a problem with the certificate, signature verification will fail.

2. The file was tampered with or damaged: imcore.dll file was tampered with or damaged during transmission or storage, which led to the failure of signature verification. This is caused by malware infection, hardware failure or file transfer error.