1. Damage during file transmission: In the process of uploading and downloading files, there may be network failures or transmission errors, resulting in damage to the integrity of files. If the signature information of a file is stored in a specific location of the file, and this part of the data is lost or damaged during transmission, the signature will be lost.
2. File format conversion: In the process of uploading and downloading, files may need format conversion, such as converting from binary format to text format or compressed format. This conversion process may cause the signature information to be lost or unrecognizable.
3. Storage or decompression: If the file is stored or decompressed into a file system or compression format that does not support signature after uploading, the signature information may be lost or unrecoverable.
4. Platform or system restrictions: Some operating systems or platforms may restrict or delete the signature information of executable files, especially in a high-security environment. This is to prevent unauthorized file execution.
What needs to be extended is that the digital signature of files is a security mechanism to verify the integrity and source of files. By signing the file, you can ensure that the file has not been tampered with during transmission, and you can also verify the publisher of the file. However, in the process of uploading and downloading files, some problems may occur, resulting in the signature being lost or unable to be verified. Therefore, when transmitting files, it is recommended to use a reliable transmission method and verify the signature after downloading to ensure the integrity and security of the files.