How to share user folder without password?

I usually work on my Dell Laptop running with Windows Vista ultimate which is connected wirelessly with my Home network. I also have a XP desktop connected with the same network via Ethernet. Since yesterday I’m trying to share my “C:\user\{account-name} folder” on Vista which can be accessed from XP as well, but every time I try accessing it on XP, it says:

“You might not have permission to use this network resource. Contact the administrator of this server to find out if you
have access permissions. Multiple connections to a server or shared resource by the same user, using more than one user name, are not allowed. Disconnect all previous connections to the server or shared resource and try again.”

I don’t know what more settings are missing. I have already turned on File Sharing, turn off password protection, but still the problem is occurring. When I checked web for some help on this, I found many guy saying that for successful sharing username and password on both systems should be same. Is that true?

Yes, it is correct. Your both computers should have the following things same:
Workgroup
Username
Password.

Apart from these, you should not have any third party firewalls installed on your computer, allow file sharing in exception list of windows default firewall. For better results, disable antiviruses.

Also,

More and more people have home networks behind firewalls. In which case the simplest and easiest security is all that's required. After all, in such environments all a user may want to do is copy their child's homework or something...

I tried dropping a link/shortcut in the Shared Folders to one of the resources I would like to share - and it worked! Thought I would need to set access permissions, but worked anyway. Just a hint...

I agree with SedX. An openminded and humble attitude and preferably with an abitity to explain in a non condescending way is the best IT admin.

This seems to be a simple solution:

1) Click on the Start/Windows button.
2) Click on Control Panel
3) a. Classsic Control Panel: Click on Network and Sharing Center.
b. Grouped Control Panel: Click on Network & Internet. Then click on Network & Sharing Center.
4) Click on Password Protected Sharing.
5) Slect "Turn off..."
6) Click Apply. (if prompted, click Allow/Continue)

Also, make sure that the folders/drives you are sharing allow ALL users FULL control, or you might still encounter these types of problems.