What should you do, if she doesn't write back, after you neg her? And if there is the possibility that she missunderstood it and thought you meant it serious?

This is the hardest part of pickup via online and text.
They don't have to answer back.

Honestly i would just not worry about it and just don't try to defend yourself because that could come off worse. Unless it was something like "oh sorry did i hurt your feelings, my bad "

If she doesn't respond to something like that then no point of messaging again and just drop her into the dead list for awhile.

I agree,... don't worry about it too much. I would not Neg her.

What is your particular situation?

Is it that she is not responding to the first message that you write, and this happens often, then look at redoing your profile, starting with your pictures.

If you are writing girls and your then they are not writing back, Check out the sticky message about direct to date... perhaps you are doing too much chat online, when you should be making the move to exchange numbers, or set up a date, and take things offline. If this is the case I would wait a few days, and say Sorry that I have not written in a while, this past weekend was crazy... (Insert a fun story of what you did, or paint a picture with your words of something cool, i.e. this weekend the weather was gorgeous, I went out iceskating with friends, under the stars, then we all went to this hip cafe, that only serves desserts and gourmet coffee, teas and hot cocoa. Everything was so fancy, my giant cup of hot dark cocoa was topped with a house made cinnamon suggar whipped cream... I even got a bit on my nose, it was piled so high.).... then go for a number exchange/close or set up a date... very confidently.
"I enjoyed our conversations so far and want to meet you up & see if we click, lets go to Lindas wine bar, on main street this tuesday at 8:30pm. "

Your profile is probably boring. She was probably just being nice to you and you either bored her or weirded her out. Post the convo.

Most of the time as a joke I'll add "*cricket chirping" this shows your conscious of the akward no reply but you can still make light of the situation and show humor and confidence, has worked for me.

PUASTL89. do you have a link to your online dating profile, i'd like to see what an awesome profile is like?

Hey man, it might be true but at least say it in a way that doesn't offend the person.

"Oh yeah, you might want to try to upgrade your profile. There's a couple of forums that help give a guideline"

My apologies if I came off offensively. That wasn't my intention. From my personal experience in helping my friends with pick up, being blunt is more beneficial. But I understand if that is not accepted on this forum.

OP can pm me if he wants examples. I won't choose to post my profiles on here.

There is also no body language online obviously. So when you're asking for help, not posting the conversation puts you at a large disadvantage. Instead of having us guess and ask a million questions on what it Might be, post your profile/pm it to one of us, and post the convo. IT will make the solution 10x easier to find.