The most common question for any IT Administrator is, How often does everyone restart their Windows servers? Is there an industry standard or recommendation? will there be any hardware or software issue if we re-start server frequently often?
Actually, Windows server has to be restarted Only when required -- Either because of an OS / software update, a critical software failure which cannot be recovered via other methods, hardware upgrade/replacement or other activity that cannot happen without a restart.
I have never seen a standard recommendation, per se, but I could not agree with any recommendation [except from Microsoft themselves] which would indicate a required reboot at a specific time interval "just-because".
I will not recommend a Windows server reboot because. Microsoft has made great strides since the good-old [NT] days with regard to stability and uptime. It's a shame the consensus within IT support has not changed along with this.
Restarting [and, more so, power cycling] is the most stressful period of hardware activity for a computer. You have most everything spinning up to 100% disk and fans as well as significant fluctuations in component temperatures.
Modern hardware is incredibly resilient, but that shouldn't be a reason for just bouncing servers, on a whim, a few times a week.
Just reboot a Windows server in the case of a failed service, or the like. I understand the need to get the service running again, but a reboot should be the last step in trouble shooting a server. Identifying, and fixing, the root cause of failure should almost never result in “just reboot it....”
However, In practice, Disk I/O, Network and Memory hungry applications under high and stressed workload and with low system resources available may render your Windows machine lagging, unstable or trashing which may suggest you to restart them sooner.
If you have to run such faulty applications or have to serve more users than the typical capacity of your hardware/software, or you are forced to co-locate incompatible services into one physical machine you may come to such decision that you should restart your Windows periodically. In this case you may adjust the restart period by listening to the users complaints about the server speed!
In my work place, We're not allowed to reboot servers without a weeklong back-and-forth debate among the entire department / Corporate Office that takes more than a week for a server reboot approval. Yes, this includes reboots for patching, which effectively means that it never gets done.