What is the most common reason of erroneous behavior of Hosting Controller?

Question: What is the most common reason of erroneous behavior of Hosting Controller? What should I check first? 

Solution:
 HC is accessed via web and for this purpose HC creates a virtual directory Admin or a site Hosting Controller on port 8787 (default) in IIS (Internet Information Services) which gives access to control panel as http://YourDomain.com/admin or http://YourDomain.com:8787. HC also sets HCAdministrator as the anonymous user for control panel, because HC requires administrative privileges for its working therefore user "HCAdministrator" is a member of Administrators group only. If the anonymous user of control panel is not "HCAdministrator" or if HCAdministrator is not the member of "Administrators" group only then this will result in erroneous behavior. It is therefore very important to check the anonymous user and its rights first before posting a problem to support or searching the knowledgebase further. 

Issues with non-english locale servers: 

In non-english locale servers, the administrators group is spelled differently. For example, in Spanish locale, the Administrators group is spelled as Administradors, therefore hosting servers on which locale is any language other than English might face the problem where HC does not add user HCAdministrator to the Administrators group only. It is therefore needed to add this user to Administrators group manually. 

Make sure that anonymous user of control panel site is "HCAdministrator", and also make sure that this site is setup correctly. 

To set/check control panel anonymous user, follow the steps below: 

1. Open IIS. To open IIS, click Start, point to Settings, and then click Control Panel, then double-click Administrative Tools, and then double-click Internet Information Services. 
2. In IIS console, click to expand your server name, and then click to expand the Web site. Select virtual directory Admin, right-click and click Properties. Alternatively, find site Hosting Controller 7C and follow same steps. 
3. Click the Directory Security tab, and then click Edit in the Anonymous access and authentication control box. 
4. Enable the Anonymous Access check box, click Edit, click Browse and select HCAdministrator user. 
5. Enable the check box Allow IIS to control password and click Ok.
   Note: After clicking Ok button, if you get any prompt, click Yes button. 
6. Enable the check box Integrated Windows authentication. Clear the check box Basic authentication (password is sent in clear text). Click Ok.
   Note: After clicking Ok button, if you get any prompt, click Yes button. 
7. Click Ok to apply changes. 

To check if HCAdministrator is a member of Administrators group, follow the steps below: 

1. Open Computer Management. To open Computer Management, click Start, point to Settings, and then click Control Panel. Double-click Administrative Tools, and then double-click Computer Management. 
2. In the console tree, click Local Users and Groups, click Groups. 
3. Double click on Administrators group and verify that "HCAdministrator" is listed in Members list. If it is listed then skip to step 5. 
4. Click Add button and select HCAdministrator user. 
5. Click Ok button. 

To check if control panel site is setup correctly, follow the steps below: 

1. Open IIS. To open IIS, click Start, point to Settings, and then click Control Panel, then double-click Administrative Tools, and then double-click Internet Information Services.
2. In IIS console, click to expand your server name, and then click to expand the Website. Select virtual directory Admin, right-click and click Properties. Alternatively, find site Hosting Controller 7C and follow same steps.  
3. Click the Home Security tab, select Scripts and Executables from Execute Permissions select-box and Low (IIS Process) from Application Protection select-box.

    4.   Click Ok button.