Apache Instrallation

[Meraj]

when I start apache than the following message is shown.
Error: Apache shutdown unexpectedly.
4:09:53 PM [Apache] This may be due to a blocked port, missing dependencies,
4:09:53 PM [Apache] improper privileges, a crash, or a shutdown by another method.
4:09:53 PM [Apache] Press the Logs button to view error logs and check
4:09:53 PM [Apache] the Windows Event Viewer for more clues
4:09:53 PM [Apache] If you need more help, copy and post this
4:09:53 PM [Apache] entire log window on the forums

What will I do for this problem?
Please help me.
Meraj]