Method 1: Use compression software.
Install compression software such as Winrar, 7-Zip, etc. on the web**.
Find the compressed file that needs to be compressed twice, right-click on the file, and select "Extract to current folder" or similar option to extract the compressed file into a new folder.
Open the installed compression software, select the unzipped folder, or drag the folder directly into the interface of the compression software.
Choose a compression algorithm in the compression software that is different from the original compressed file, and you can also adjust options such as the compression level if needed.
Once you are done with the settings, click on the "Start Compression" or similar button and wait for the compression process to complete.
Method 2: Change the compression configuration or level.
Right-click the file you want to compress on your computer and select the Add to Compressed File option.
In the pop-up compression configuration, click the [Compress Now] button to complete the first compression.
Open the first compressed package, select the file that needs to be compressed twice, and right-click and select Add to Compressed File.
In the pop-up compression configuration, you can change the compression configuration, such as selecting the Smallest Volume option, or changing the compression level to Extreme Compression.
Click the [Compress Now] button to complete the secondary compression.
The above two methods can achieve secondary compression of compressed files, but it should be noted that secondary compression may cause some damage to the file, especially for some files that have been highly compressed, the effect of recompression may not be obvious, and it may even cause the file to not be used normally. Therefore, it is advisable to back up the original files before doing the secondary compression to prevent unnecessary loss.