0 Cannot open file for writing log

Hello all, I imported my joomla files and Db from a site that I've done in local using wamp.
I cannot make it work properly online. I can access to my site even without digit username and password and this message it's continuing to pop over the contents of my site. I am only able to see the main Menu and Log's stuff.
I set the absolute path properly and all the rest seems allright to me.
I am a new user of Joomla and running version 3.2.1.
Anyone knows how to fix this issue?
I have try to follow some guides online but no fortune in it.
Please help me. Deadline is coming and would like to test it and see it properly work before to publish it!!!
Thanks a lot for all the support u could give me guys!
Regards!

[Gianluca]

fdgtesting:

can you please paste the full text of the error message? Is there any path displayed?