folder permisions & Undefined variables

[gareth]

I was playing around with GS for the first time over the weekend, and installed with ease. The first time I ran the install an error message came up advising me to check certain folders were set to (777) as well as the data folder being set to (755) (if i remember correctly, it was quite late!)

I have come into work today to show my colleague what I had found, and tried to install on a different location. This time I am not seeing the helpful message? Can anyone tell me which folders should have what permissions?

I am also seeing error messages as follows, but hope these are to do with permissions?

Notice: Undefined variable: SITEURL in /home/****/public_html/cms/admin/inc/common.php on line 87

Notice: Undefined variable: SITENAME in /home/****/public_html/cms/admin/inc/common.php on line 90

Notice: Undefined variable: LANG in /home/****/public_html/cms/admin/inc/common.php on line 108

Warning: Cannot modify header information - headers already sent by (output started at /home/****/public_html/cms/admin/inc/common.php:87) in /home/****/public_html/cms/admin/inc/common.php on line 129