What are the advantages and disadvantages of creating a Windows service

Advantages:

• It is controlled by the operating system and can start automatically in boot or on demand or restart when there is a failure and can be done remotely directly
• You do not need a logged in user to run it and it can impersonate other users
• Have more control over security and access control
• Not visible
• Can not be closed by normal means, but can be controlled even better than a normal application, including easily stopping a hanging process, and can control and monitor all this

Disadvantages:

• Can not run more than one instance
• Usually needs administrator privilege and needs an installation of it and of course, an update is not as simple as overlapping an executable
• It is more complicated to develop and debug, if you can not do it right and understand what has to be different can be problematic (not usually a good idea for those who do not master software development very well unless they do something trivial)
• Does not interact with user

You need to know the entire API of the services and the peculiarities that it requires.

Just complementing what Maniero said:

Maintenance level: Maintaining a service (from my point of view) is as simple as a VCL application. Since the service typically runs on only one machine, upgrade issues are rare. Having a legal plan for updating (not making changes at the time the service is most used) is a great start. The code used in a visual application is the same as that used in a service. So there are not many problems about that. For debug I particularly find it annoying. In my cases, I had to create compilation directives for these situations, nothing too complex, just "boring".

Problems faced:

1: Problems trying to install service through command WinExec (I was able to resolve using ShellExecute ) #