Thanks for answering. I've always provided a doctor's sicknote everytime I've either been off sick or needed half a day at an appointment. Like I said already, I'm happy working under my manager. So I'll take this on the chin and give advanced notice next time.

-1 "stop missing meetings" So, by your standards, if a person had meetings every day, then they should never go to the doctor? I've had managers with meetings 80-90% of their day, so if they can't miss a meeting they can't see a doctor? With medical problems being a major part of the last 3 years, it's pretty draconian to think going to a doctor, even on short notice, is unacceptable. Do you know you're going to have 24 hrs notice for the flu or food poisoning, or twisting an ankle getting out of the shower, or sliding down a wet flight of stairs, or a sick child?

@computercarguy, you'd rearrange your meetings, with sufficient advance notice to people (and "sufficient" is a matter of judgment, but it's certainly something more than zero notice and just failing to turn up).

@computercarguy "it's pretty draconian to think going to a doctor, even on short notice, is unacceptable" - it only requires spending a very small amount of time on comprehension to know that this is not what is being said. If a staff member is not giving as much notice as possible, and it's having a real effect on the workplace (being expected to be in customer meetings means their absence creates a lack), then that is a problem that should be addressed.

@RobGrant, in a comment on nvoigt's answer, the OP said they didn't know about the client meeting until after it happened, so there's a lack of notification on the employer's part, too. Even in the US, where laws are stacked heavily for the employer, taking time off for sickness with little to no notice is acceptable, and getting fired for it would be a lawsuit in all but the most extreme cases of obvious lying by the employee. "Having a real effect", really? Sounds like the meetings went on just fine. And any absence can have a "real effect" to a deadline, so again, not a good enough excuse.

@Steve, not all meetings can be rearranged, especially in a corporate setting where there may be higher management that doesn't have the ability to change their schedules. And the OP said they did give notice in the morning. Plus the comment on nvoigt's answer said they didn't even know about the client meeting until afterwards. If anyone was going to "rearrange" a meeting, it should have been the manager who rescheduled the impromptu client meeting for when the OP could attend.

@computercarguy, re your comment to RobGrant, I'd missed the OP's additional remarks when drafting my answer. Obviously, the OP can't be penalised for not attending a meeting he didn't know about (unless he had reason to expect it might occur - it's difficult to be comprehensive about all possible circumstances). But I'm getting the impression that the OP might lacks a certain acuity in general, unless it's a language barrier or something - because any sensible person would have phrased the situation as "I'm being accused of missing a meeting I was never told about!".

But I'm getting the impression that the OP might lacks a certain acuity in general, unless it's a language barrier or something - because any sensible person would have phrased the situation as "I'm being accused of missing a meeting I was never told about!" damn, everyone's taking shots at me.

@computercarguy, re your comment to me, obviously it's no longer clear what the situation was in regard to the missed client meeting, or how important his attendance actually was. But without more justification, I'm inclined to consider the OP unreasonable for taking the day off without prior notice. If you have a relatively new employee who is not just proving to be sickly, but who also seems to be becoming somewhat impulsive with absence and careless with communication, without there being an acute medical justification, then the employer's behaviour seems consistent with that.

@Duzii2, I can only call it as I see it. As I say, there may be a language barrier. Or you may be withholding pertinent details out of privacy concerns. And your behaviour and attention may be influenced by concern about your medical condition. But impression I have is that your behaviour is not fully explained and doesn't fully make sense - not just in terms of events at work, but in terms of why you'd forget/omit crucial details here that change the situation significantly (such as whether or not you even knew about the meeting you were accused of missing).

@user3700562 and you come across as having a massive ego and pride. Don't take everything as a personal attack. Sometimes life happens. It doesn't mean someone is deliberately trying to offend you.

@Duzii2, is my ego and pride not big enough to also deserve a mention?

Kinda proving my point with your answer though. No offense, but you lack insight. You still think your behavior was acceptable. The reality is your employer expects you to pull your weight, that's what you are being paid for. Repeatedly missing meetings on short notice as the new guy just won't leave a good impression, like it or not. You are the one who shouldn't take comments from random strangers on the internet as personal attacks. Just giving you my opinion on what I would think of you if I were your boss.

@Steve compare what you wrote to what random user wrote. He was being unnecessarily aggressive.

@Duzii2 It seems that user3700562 is picking up the same signals that I and some other commenters here see. You seem to be totally unaware of (or uninterested in) the effects of your behavior on others in your workplace. You do not seem to understand, at all, why your manager is unhappy. It is not because you were absent. It is because you knew you would be absent but did not inform anyone until the very last moment.