Before you post a question in the forums, you will save yourself and everyone else a lot of time by having the details of your configuration ready, and putting it right into your first post.   Here is a good way to get some diagnostic information that will make troubleshooting much easier.

1.  Your Joomla Configuration.  Use the "System Info" utility, available in both Joomla 1.0.X and Joomla 1.5 to gather basic environment information. This utility can be found under the "System" menu, as shown below:

This will give you an output that includes things like PHP version, Database version, and more.  Just copy the entire first tab and third tab (permissions), and paste them into your forum post. 

2.  PUArcade. Click on the Maintenance button from the main control panel.  Click the button labeled "Support Diagnostics".  It will ask if you are sure, click "Yes".  It will come up with your PUArcade version, and some other stuff.  Copy all that, and paste it into your forum post.

3.  Verify that your PUArcade system bot is installed and enabled.  You can do this by using the Joomla plugin (or mambot) menu, depending on your particular version of Joomla.  Post the status with your quesiton.

4.  If you are using any SEF/SEO components, post their names with your question. 

5.  If you are using any Joomla hacks or bridges, post their names with your question.  It is especially important if you are using an SMF bridge.

6.  If you are using JAccelerator, post such, along with a version.

7.  If you can, post a link to the page where the issue is occuring.   If you cannot post a link, post a screenshot.

8.  Enable error reporting.  This can sometimes reveal errors you aren't seeing, especially if you are just getting a blank screen.  Do this by editing your Joomla configuration.  Set your error reporting level to "Maximum", then try to duplicate the issue.  Be sure to note in your forum post that you did this, and include any error messages that were revealed.