: Since you are using a Portable version of CS4, ensure you are saving your work to a stable directory (like your USB or a dedicated local folder), as portable versions can sometimes have issues with temporary scratch disks. How to Create a Notebook Page in Adobe Illustrator
If you need true portable Adobe software with proper licensing, look into: Adobe Illustrator CS4 14.0.0 Portable
: Go to File > Save As and choose Adobe PDF for a high-quality, print-ready version. : Since you are using a Portable version