Errors Stop Sitemap Generator

[azmortgages]

The generator will index about 1900 out of 2000 pages and stop. These are the error messages.
Warning: file(/home/arizonac/public_html/generator/data/sitemap.xml) [function.file]: failed to open stream: No such file or directory in /home/arizonac/public_html/generator/pages/class.utils.inc.php(2) : eval()'d code on line 40

Warning: implode() [function.implode]: Bad arguments. in /home/arizonac/public_html/generator/pages/class.utils.inc.php(2) : eval()'d code on line 40

10 - 15 minutes after generator stops, I'm given the option to resume crawling.  After checking the resume crawling box, the generator finishes building the sitemap.

[admin]

Hello,

make sure that you set 0777 permissions for generator/data/ folder.

[azmortgages]

yes,  generator/data was at 0777
I'm not able to generate a new site map at all now even though it runs and I get a 'completed' message. However the site map is old. Here's the error message on the 'view sitemap' page:

View Sitemap
HTML SiteMap
[external links are visible to admins only]
Text SiteMap
[external links are visible to admins only]
ROR SiteMap
[external links are visible to admins only]

Warning: file(/home/arizonac/public_html/generator/data/sitemap.xml) [function.file]: failed to open stream: No such file or directory in /home/arizonac/public_html/generator/pages/class.utils.inc.php(2) : eval()'d code on line 40

Warning: implode() [function.implode]: Bad arguments. in /home/arizonac/public_html/generator/pages/class.utils.inc.php(2) : eval()'d code on line 40
1. XML SiteMap File
[external links are visible to admins only]

[admin]

Make sure that you created empty "sitemap.xml" file in domain root as described in installation instructions and set 0666 permissions for that file.