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As an active LinkedIn networker, blogger and trainer, I receive lots of LinkedIn questions every day. This week, there seemed to be a common theme – LinkedIn Invitations. Many interesting questions crossed my desk, so I thought I’d compile them all in one place and share my answers with you. Have a question about LinkedIn invites? It’s probably answered below… Take a peek!

1. What’s the best way to invite someone to connect?

I always tell people to never send an invitation unless you’re fairly certain it will be accepted. A best practice is reach out to that person elsewhere first (email, phone, real life conversations, Twitter, Facebook, Google+, LinkedIn messages, InMail, group discussions, status updates, etc.) and start a conversation. If they seem amenable, go ahead and invite them (customizing the invite to remind them how you know each other and why you’d like to connect).

Never send the default invitation verbiage since it does turn off some people. And definitely don’t bulk-invite everyone in your email contacts list. There’s no way to personalize the message and it could lead to some invites that you probably didn’t intend to send (your ex-spouse, grandma, doctor, mechanic, that employee you fired, people who might not know you or remember you and/or people who aren’t even on LinkedIn – but will now get marketing emails to join LinkedIn… something they may not appreciate at the end of the day).

2. How many invitations can I send?

You are allotted 3000 invites to send out and you can send out as many as you want per day, but you will be required to enter a Captcha for each invite over 100 sent in a 24-hour period.

3. How can I prevent accidentally inviting the same person more than once?

If you’ve already invited that person, you will no longer see the regular “Invite John to Connect” screen with the gray box and the radio button list. You will instead see a similar screen with only one option – to invite that person by plugging in their email address. This screen tells you that you’ve already invited this person in the past.

4. Can I withdraw an invitation once I’ve sent it out?

Yes, simply go to Inbox > Sent > Sent Invitations tab to see all of your sent invitations. Click on any invite you want to withdraw to open the message then click the “Withdraw” button. The person will not be notified that you’ve withdrawn the invitation. (If you want to find a specific invite to withdraw, go to the search box in the top right corner of any screen, choose Inbox from the dropdown menu, plug in the name of the person you wish to un-invite and it will pull up that specific invite in the search results).

5. If I withdraw an invite, is it credited back to my account?

Nope, I’m afraid not. Once you’ve sent an invite, it counts toward your 3000 invitation limit whether you withdraw the invitation or not.

6. What do I do if I run out of invitations?

Simply email LinkedIn Customer Service and ask for more invites. As long as you haven’t been labeled a spammer by getting too many declines, they will typically grant you another 500 – 1000 invites (per month) to send out. If you use them all up, you will need to wait until that month is up before asking for more.

7. Why would I ever want to withdraw an invitation?

I recommend withdrawing an invite if it hasn’t been accepted in the past week or so. It means that either a) the person doesn’t remember you, b) they don’t want to connect with you for some reason or c) they aren’t very active on LinkedIn (and may not remember you by the time they do log back in… which greatly increases the chance that you’ll get declined).

8. What happens when someone clicks “I don’t know John?”

Many people don’t realize this, but this type of decline is EXACTLY the same as getting marked as Spam. IDK (I Don’t Know) and Spam are identical in LinkedIn’s eyes and if you receive approximately 5-7 of these declines (either type, in any combination), then LinkedIn will place a restriction on your account, requiring you to enter an email address for all future invites.

9. Why is LinkedIn requiring me to enter an email address to invite people?

It means you’ve received too many declined invitations and LinkedIn has placed a restriction on your account. (See #8 above.)

10. How can I remove a restriction on my account?

It’s not uncommon for newbies to get overzealous with their invitations and get restricted, so LinkedIn has actually created a way for you first-timers to remove your own restriction. Simply go to this page, check the “I agree” box and click “OK.” Shazam! You’re now unrestricted and back in action. (Just be more careful going forward!) Not your first restriction? You’ll need to reach out to Customer Service and promise to be more careful with your future invites.

11. How can I tell if someone’s marked my invite as IDK / spam?

Here’s a little ditty that I discovered a while back but this is the first time I’ve shared it with anyone else! :) When you click on a sent invite (see #4 above), if the “Resend” box is missing, that means the person has archived your invitation (which does not penalize you in any way aside from taking up one of your 3000 allotted invites). If both the “Withdraw” AND “Resend” buttons are missing, it means that the person has marked your invitation as Spam or IDK. (Note – it could also mean that you’ve already withdrawn the invite or they’ve already accepted it, so always delete a withdrawn invitation for record-keeping purposes and/or check to make sure they’re not already a 1st level connection. You can’t reinvite someone who’s already connected to you!)

12. How can I prevent account restrictions in the future?

Stick to those best practices outlined in #1 above. Only send an invite that you’re fairly certain will be accepted. Never roll the dice with an invite. Start the conversation elsewhere and only THEN send an invite to connect. Customize the invite, be clear how you know each other and let them know why you’re interested in connecting. These best practices will greatly increase your acceptance rate!

Even better? Create a one-click invitation link that takes people directly to your invitation page on your LinkedIn profile. Feature this link anywhere that prospective connections might read it (your email signature, blog, website, Twitter bio, Facebook page, company website, About.me page, etc.). The best part? A one-click invite reaches a wide audience, puts the ball in the other person’s court to invite you (rather than putting them on the spot with an invite), doesn’t use up any of your 3000 invites (since the other person is inviting YOU) and there’s no risk of you getting declined as Spam or IDK (since you’re the one doing the accepting, not the inviting). Cool, huh? (Feel free to comment below with YOUR one-click invite link… you just might get an invitation!)

Any questions I left out? Any additional tips or personal anecdotes you’d like to share? Let us know!

Stacy Donovan Zapar is a 15-year recruiting veteran and CEO of Tenfold Social Training, a training / consulting company for recruiters and hiring teams. She is also the Most Connected Woman on LinkedIn with more than 36,000 first-level connections. She served as Technical Editor for Wiley’s LinkedIn Marketing: An Hour a Day and is a regularly-featured contributor on The Undercover Recruiter. Feel free to follow Stacy on Twitter @StacyZapar and connect with her on LinkedIn.