UPX-MCS

UPX-MCS is a Windows batch utility for aggressively compressing .exe files with UPX.

It remembers your UPX executable path, keeps a rolling history of the last 5 executables you compressed, and preserves an uncompressed backup beside the original file before packing.

What It Does

• Prompts for upx.exe the first time you run it, then saves that path for future runs.
• Lets you pick from the 5 most recently compressed executables or enter a new path.
• Renames the original file to *-uncompressed.exe.
• Copies the backup back to the original filename.
• Runs UPX using:
  • --best
  • --lzma
  • --ultra-brute
  • --compress-exports=1
  • --strip-relocs=1
  • --overlay=copy
  • --force

Files

• compress.bat
  • Main compression script.
• upx_path.txt
  • Stores the last valid path to upx.exe.
• packed_history.txt
  • Stores the 5 most recent executable paths.
• UPX-MCS-help.txt
  • Plain-text quick help.

Requirements

• Windows
• UPX
• Permission to rename and copy the target executable

How To Use

1. Run compress.bat.
2. If prompted, enter the full path to upx.exe.
3. Choose a recent executable from the menu or press N to enter a new one.
4. Wait for the script to create the -uncompressed backup and compress the original filename.

Output Behavior

If you compress:

C:\Apps\Tool.exe

the script will:

• Rename it to C:\Apps\Tool-uncompressed.exe
• Recreate C:\Apps\Tool.exe
• Compress the recreated Tool.exe

Notes

• The history list shows only the most recent 5 entries.
• Recompressing a file moves it to the newest position in history instead of duplicating it.
• upx_path.txt and packed_history.txt are machine-specific runtime files and are ignored by git.
• Always test your packed executable after compression. Some executables do not behave correctly after aggressive UPX settings.