I saw your other post and realized you already tried the memory bump plugin. On to Step 6:
PHP.ini is the php configuration settings file. I uploaded a php.ini file to the pastbin you can use but please acknowledge my warning.
The memory limit is on line 232 and is set at 64MB. This should be enough but it can be raised or lowered if needed.
To determine the proper settings create a file with this code in it:
Save this file as info.php and upload to your public_html directory and go to a web browser and go to http://yoursite.whatever/info.php
Here is a sample of what this will look like when you run it: http://luckyco.com.tw/sample/phpinfo.php
You need to get the include path, extension directory, and sendmail path from your files output and make the changes to the php.ini file I provided.
Please note that your hosting provider is taking advantage of you and giving you HORRIBLE customer support and any host worth a crap would do this for you in a heartbeat. Especially if it is just to raise the allowed memory.
Without knowing the specifics of your hosts server configuration this might cause some server errors. Line 411 through 435 must be confirmed with your host or via a phpinfo() or it will not work!!
Here is the file: http://wordpress.pastebin.com/D4xB3iJY
Upload the php.ini to the root WordPress directory
Please confirm with your host the directory paths needed in the file and make the changes.