Step 1:  Check for add-ons

1. Check if add-ons are present under the folder path <APM home>/working/. If it is not present, then download the add-ons and place it in the mentioned path.
   
1. Refer here to know more about prerequisites for adding Webpage Analyzer monitor.
   
2. Once the add-ons are placed properly, check if pagespeed_bin file is present under <APM home>/working/wpaAddons/PageSpeedInsights/ folder.
   

Step 2:  Run pagespeed_bin command

1. Open terminal from <APM home>/working/wpaAddons/PageSpeedInsights/ folder.
   
2. Run the following command and check if it returns any result. (attached a sample screenshot below)
   

<APM home>/working/wpaAddons/PageSpeedInsights/pagespeed_bin

                  

1. If it returns "Permission Denied", grant permission by executing the following command and check again
   chmod a+x  <APM home>/working/wpaAddons/PageSpeedInsights/pagespeed_bin
   
2. If it returns "No such file or directory" follow Step 3
   

Step 3 : Find dynamic loader required 

1. Run the following command and check if it returns loader names.
   ldd <APM home>/working/wpaAddons/PageSpeedInsights/pagespeed_bin
2. If it returns "not a dynamic executable" run the following command to install the library. Once the library is installed run the previous command and check if it returns loader names now.
   sudo apt-get install gcc-multilib
3. Sample Screenshots
   

     

1. If any loaders are marked as not found, install those libraries.
   
2. Now again execute the below command and check if it returns the the result as mentioned in Step 2.
   <APM home>/working/wpaAddons/PageSpeedInsights/pagespeed_bin
   

If the issue still exists share the below information for further analysis

1. Result of executing pagespeed_bin command.
   
2. Support information file.