No, the new installer should recognize a previous installation, remove it and install the new one.

No, HealthMonitor includes an internal reloader.

The "AppConfig.Config" file (in the HealthMonitor website directory) is modified during installation. Please check that this file can be modified by the Network Service account (IIS 6.0) or by the ASPNET account (IIS 5.0); if not, change their permissions as appropriate. Check also the "HMLogger\Configuration" subfolder: it must be writable too.

You can install IIS from "Control Panel"-->"Add/Remove Programs". Please choose "Add/Remove Windows Components", select "Application Server" and click the "Details" button; select "Internet Information Services" and click "Details" again; make sure that the "World Wide Web Service" option is checked. Press "OK" and "Next" to complete installation.
You can download an example here.

This error occurs when the ASP.NET Extensions are missing or prohibited in Internet Information Server.

1) Please check that ASP.NET extensions are installed in IIS: open IIS Manager and reach the "Web Service Extensions" section: "ASP.NET v2.0.50727" should be listed here. If it is not listed, you can install it by issuing the command "aspnet_regiis.exe -i -enable" at the command prompt.
You can download an example here.

2) If ASP.NET extensions are installed, please check that they are enabled. You can do that in IIS Manager: reach the "Web Service Extensions" section, select "ASP.NET v2.0.50727" and click the "Enable" button.
You can download an example here.

This error occurs when the ASP.NET Extensions are prohibited in Internet Information Server.
You can enable them in IIS Manager: reach the "Web Service Extensions" section, select "ASP.NET v2.0.50727" and click the "Enable button".

This could occur if you didn't enable ASP.NET 2.0 within the HMWeb Virtual Directory.

Enable the .NET Extensions on IIS.

Check that appropriate permissions are set on the HealthMonitor Web Interface website directory (read permissions for the Internet Guest account).

HealthMonitor 5.0 works on Vista. Version 4.0 works on Vista, but you need to right click on Interface.exe and select Run As Administrator.

This is due to the ASP.Net configuration. If you are using ASP.Net 2.0, make sure that the Windows account used for ASP.Net has permissions to access the metabase. The IIS Registration Tool in ASP.Net (%Systemroot%\Microsoft.NET\Framework\v2.0.xxxxx\aspnet_regiis.exe) with the ga option allows you to set this configuration. For example, the following command grants authorizations to the Windows user ASPNET in the IIS metabase:

aspnet_regiis –ga ASPNET

For a different solution, you can reconfigure ASP.Net like that:

aspnet_regiis –u (removes the ASPNET component in IIS)

aspnet_regiis –i (performs the ASPNET component installation in IIS)

To restrict access to the web interface, you can set the basic authentication on the "config" subfolder in the HealthMonitor web interface installation folder. You can do that in IIS: in IIS Manager, select the HealthMonitor website, select the "config" directory, choose "properties", "directory security", disable anonymous access and enable basic authentication. You should do that on the "config" directory only, otherwise the clients won't be able to connect to the web interface.

Open the AppConfig.Config file in the HMWeb directory and look for the following line:

<add key="LoggingEnable" value="False" />

Please change "False" to "True" (you may have to restart IIS for that to take effect) and try installing again the HealthMonitor Client. HealthMonitor will generate a log file (\hmlogger\configuration\temp\log.txt), it may include useful information which can help you solve the problem you met.