Ping uses name resolution to resolve a computer name into an IP address.

Therefore, if you successfully ping an IP address but you cannot ping a computer name, there is a problem with host name resolution, not with network connectivity.

• Verify that DNS server addresses are configured for the computer, either manually in the properties of TCP/IP, or by automatic assignment. 

Try to ping the dns server addresses(DNS server addresses are listed when you type the ipconfig /all command) to make sure that they are accessible.

 if you cant ping you have to set right dns server adresses.

to check Windows for 32-bit OS or 64-bit OS :

Start --> Run --> msinfo32.exe

System Type :

• For 32-bit editions of Windows : x86-based PC.
• For 64-bit editions of Windows : x64-based PC.

OS Name    Microsoft Windows XP Professional
Version    5.1.2600 Service Pack 3 Build 2600
OS Manufacturer   
System Name    
System Manufacturer    
System Model   
System Type    X86-based PC
Processor    x86 Family 6 Model 15 Stepping 13 GenuineIntel ~1994 Mhz
BIOS Version/Date    COMPAL 1.16, 12/31/2007
SMBIOS Version    2.4
Windows Directory    C:\WINDOWS
System Directory    C:\WINDOWS\system32
Boot Device    \Device\HarddiskVolume1
Locale    
Hardware Abstraction Layer    Version = "5.1.2600.5512 (xpsp.080413-2111)"
User Name    
Time Zone    GTB Daylight Time
Total Physical Memory    2,048.00 MB
Available Physical Memory    1.03 GB
Total Virtual Memory    2.00 GB
Available Virtual Memory    1.96 GB
Page File Space    3.84 GB
Page File    C:\pagefile.sys

Cause

When you use merge statement

Action

 You have to check primary key constraint for two tables in merge statement.

oracle alert log

22344 redo blocks read, 55450 data blocks need recovery

there is no response in server 

you should :

startup mount;

recover database;

alter database open;