hello ,consider the situation:
PRODUCT: ps cs5
printer: epson profession v500 photo scanner.
os: mac os 10.8.2 (64 bit)
Printer not getting detected:
run Photoshop CS5 in 32-bit mode:
1. Quit Photoshop CS5.
2. Navigate to Applications/Adobe Photoshop CS5 folder.
3. Select the Adobe Photoshop CS5 application
4. Choose File > Get Info.
5. Select "Open in 32-Bit Mode".
6. Close the Get Info dialog box.
7. Restart Photoshop CS5
That would mean that your printer driver has a problem (probably really out of date) -- it should be working in 32 and 64 bit applications.