What will I do to make my clients reply to my e-mails?

Don’t send them one-sentence e-mails.

Welcome to Fluther.

This is a question that just cries out, in a very faint, plaintive, sort of wailing voice from way out in the wilderness for “detail”. I.e., what business are you in, who are your clients, and why is it vital that they reply to your emails?

I work in the home office (well, the US home office, anyway) of a multinational engineering-construction company. I deal with our field management people in jobsites all over the world (currently all on “the other side of” the world). When I write emails to them I almost never expect to “hear back” from them; I only want them to do something that will enable them to continue receiving service from our IT people, make crucial upgrades in their computers and messaging systems, be able to continue filing expense reports, and such like that. It hardly matters to me whether they write back unless my instructions are unclear, the recommended actions cause or will cause problems, or something else is wrong.

When I need to get a response, such as “What is your computer name? The IT people have to know, and I don’t have it in my own records,” then I write that every day until I do get a response, or I call them at home, when my day is just starting.

Contrary to @fremen_warrior‘s advice, I suggest you make the follow-up emails very short. “I need an answer to yesterday’s / last week’s question. Please respond.”

But not knowing anything about you or your business, I’m wondering why it’s so important that your clients reply.

Also be sure to cc the email to someone else either at your side or the client’s.

I have noticed that,people hardly ever respond to emails anymore even businesses, you always have to follow up with a phone call. I love email as I am not a phone person but it has become virtually useless.
What I do is, I type in the subject line.. “I Need a Response ASAP”

I agree with @CWOTUS, I would need more information to answer this question. Who are you emailing and why?

I also don’t think you can ‘make’ your clients reply to your emails. You can only encourage them to respond. At the moment you are obviously not doing that.