What system configuration you have ?
Below is the rquirement to run LR 4
Windows
- Intel® Pentium® 4 or AMD Athlon® 64 processor
- Microsoft® Windows Vista or Windows 7 with Service Pack 1 or Windows 8
- 2GB of RAM
- 1GB of available hard-disk space
- 1024x768 display
- DVD-ROM drive (if installing from DVD)
- Internet connection required for Internet-based services*
Mac OS
- Multicore Intel processor with 64-bit support
- Mac OS X v10.6.8, 10.7, or v10.8
- 2GB of RAM
- 1GB of available hard-disk space
- 1024x768 display
- DVD-ROM drive (if installing from DVD)
- Internet connection required for Internet-based services*
