If you see the error message “End-of-central-directory signature not found” while trying to unzip a file using the unzip command, it usually indicates that the compressed file may be corrupted or in an incorrect format.

There are generally two possible reasons for this error:

1. The file exceeds 2GB in size, which is a limitation of the unzip command, preventing it from decompressing larger files.
2. The compressed file was corrupted during downloading or transmission.

Here are some solutions to address these issues:

1. Redownload the Compressed File: Try to download the file you want to unzip from the original source again. Sometimes, files can get corrupted during the transmission process, which can lead to unzipping issues.
2. Check File Format and Compression Method: Ensure that the file format and compression method are compatible with the unzip command. For example, if you are trying to unzip a .zip file, you should use the unzip command rather than tools like tar or gzip.
3. Use Alternative Unzipping Tools: If the unzip command still fails to extract the file, consider using other extraction tools such as 7-Zip or WinRAR to decompress it.
4. Attempt to Repair the Compressed File: There are tools available that can attempt to fix corrupted compressed files. For example, the command zip -FF filename.zip --out repaired.zip can be used to try to repair a damaged .zip file. Keep in mind that this method of repair might not always work, but it may succeed in recovering some files.

I hope these solutions help you resolve the error message encountered with the unzip command.