Is it a good idea to write an inquiry email to professors when applying for a Masters program in Europe and Asia?

Question

I have read a lot of suggestions on mailing professors beforehand when applying for PhD. I, however wanted to know if the same strategy applies to a Master's program too?

I have been a professional for a few years, and I am applying for Masters in some top universities in Europe (Germany, Netherlands, Sweden) and Asia (South Korea, Singapore, HK) in CS (specializing in Data Science or Machine Learning).

However, I don't have any research based credentials and I became interested in research as part of my job and I want to maximize my chances of being accepted into a program because I have a poor CGPA (also failed in some core courses but managed to graduate in time) and NO academic recommendations (I have only professional recommendations). Also, I don't have any specific research idea - I would probably just work on what the professor is working on.

I had tried last year for Masters programs in the USA but got rejected everywhere. I don't want to repeat the same again.

Does it help at all mailing particular professors asking them if they are taking Masters students in the coming year?

Edit: I am applying for Research based masters because over the years I think I have more than made up for my poor grades by taking lots of MOOCs.

EDIT 2
What it eventfully boils down to is given that I HAD a slightly poor record, NO academic recommendations, BUT a great PROFESSIONAL record and a drive for learning...how do I MAXIMIZE my chances in for a RESEARCH based MASTERS program?

Answer 1

In Germany individual professors are not involved in the admission of Master students. So if you're hoping that it will positively influence your chances, there's no point.

Answer 2

You have nothing to lose by emailing professors, provided that you go about it in the right way.

Professors get a lot of email, and anything that looks vaguely spammy is highly likely to be ignored. So don't email every professor in every department you want to apply to with the same cut-and-paste email. Find out which professors are doing research that you're interested in (perhaps by looking at their website or a couple of their recent papers) and write a short, polite email explaining who you are and why you would be interested in studying with them in particular. Possibly also attach your CV.

Don't simply ask them if they are taking students in the coming year, as you will only get a "yes" or "no" answer, with no opportunity to start a conversation about research, which is what you want.

You may not get a reply, or you may get the standard "Thanks for your email, I encourage you to apply to the programme" reply. You may have to wait for a long time to get a response (perhaps after two weeks, send one short follow-up and then leave that person alone). It also depends on the typical procedures of the specific field, country or university. Some will expect you to have the support of a potential supervisor (and possibly to have even drafted the research proposal with that supervisor) before sending the formal application. Check what is expected before sending your first email, and write it accordingly.

Finally, since you say you have been working in industry for a few years, I don't think having no academic recommendations will harm you overmuch, but it could be worth getting in touch with your tutor or Bachelor's dissertation supervisor (if you had one) to explain your plan to do a research-based Master's and ask if they would be able to write you a strong reference letter.