When I connect to another computer by using IP address as(e.g) \\10.10.10.10 I get error message that Workgroup is not accessible, you might not have permission. Haw can I solve this problem ?

Can you ping the computer that you're trying to access?

From a command prompt type ping 10.10.10.10. If you're connection is good you should see a Reply message when you do this.

The answer is in the error message... you are in a workgroup, and there is no tructed connection to the machine. You are best off going direct to a share AKA: \\10.10.10.10\share