Sims don't arrive at travel destination

@Saddy-chin  What are your computer's specs?  Some people with less RAM and/or integrated graphics cards need to take steps to ease the travel transition.  This can also apply to worlds that have been played for several generations and have built up large amounts of data.  To lessen the demands of traveling, you can save, quit to desktop, and reload immediately before your sims travel (and immediately before they return as well), and also turn your graphics settings all the way down until you can confirm that the sims have arrived safely.  (Then you can revert the settings to normal.)  Having fewer items in your sims' individual inventories helps as well.

It might also be useful to clear the five cache files in your game folder, especially if you do not do so regularly.  For reference, they are:

CASPartCache.package

compositorCache.package

scriptCache.package

simCompositorCache.package

socialCache.package

There are more ways to troubleshoot, but this is a good place to start.  If the above steps don't work, please post back with your computer's specs and the state of your current save file (how much in-game time have you played it, how many sims in the household, which ones are you trying to send on vacation).

My family inventory is empty. And the sim inventory only holds stuff for tomb raiding. (food, keystones and a tent).

I set my graphics settings all the way down. No success, unfortunately.

How do I clear the cache files? Do I need to delete them? Or replace them?

My computer specs:
Win 10 Home 64-bit
Intel Pentium CPU G4600 @ 3.60GHz

8 GB RAM

graphic card: NVIDIA GeForce GTX 1050 Ti

(I hope that is what you mean .. Forgive me for being a tech noob v.v)

My family consists of five sims. Four are young adults, one is a child. First I tried to send the adults only. I thought maybe I can't leave the kid alone. But no matter who I send, it doesn't change anything. I've been playing with that household for almost 70 hours.

@Saddy-chin  Alright, your specs look fine.  Although I hope you've taken steps to cap your in-game frame rates?  (If not, you should do that before anything else, although there's a chance it could help this problem as well.)  And yes, just delete those five cache files, but not any others.  You can delete everything in your FeaturedItems folder as well.  And definitely make at least copy of your save so that you have a backup.  You can do this in-game by using "save as" instead of saving and renaming it, or you can right-click on the save in your game folder and then copy and paste it somewhere else safe.

Also, at least for the time being, play offline (run Origin in offline mode, don't sign in at the launcher or Main Menu), disable the in-game shopping experience and the hidden object game loading screens... memories are a resource hog, but you probably have a lot of them.  If you don't have the patience to clean them out on your existing sims, fine, but in the future you might want to consider turning them off.

So again, load up and try the travel transition.  If it doesn't work, quit to desktop, reload, and try with just one sim.  (You don't have to save this; just let me know if it works.)  It would also be helpful if you tried a different travel destination, to find out whether it's the world you're sending your sims to or the travel mechanic itself that's causing all of these issues.

There are more things you can try, but let me know if any of this changes things.  That will help determine what to do next.  Oh, and if you've done anything to edit the destination world, that would be good to know as well.

Almost forgot, what world do your sims live in now?  It might not matter, but it's worth checking out.  And which other packs do you have in play.  Each one adds to the game's overhead, lessening the resources left over to load both the home and destination worlds.

How do I cap my in-game frame rates? I will try this before clearing the cache.

I have the in-game shopping, the memories and the hidden object loading screen disabled from the very beginning.

I have only edited a tomb in France. But I can't travel to neither France, China or Egypt.

My sims live in Island Pradiso. I have... eh... almost all major expansion packs. Ambitions, Late Night, World Adventures, Supernatural, Showime, Seasons, Pets and Island Paradise. Oh, and Dragon Valley. I don't have any accessoire-packs. The only items I bought from the sims shop are a violin and a house. But sims always worked on my old computer, even with a ton of clothes and hair styles I downloaded (I don't have them anymore and I don't plan on getting them again)

@Saddy-chin  You can see the in-game frame rates by bringing up the cheat console (crtl-shift-c) and then entering "fps on" without the quotes.  A number will appear in the upper right corner of your screen.  "Fps off" will make it go away.  The fps you see should never go over 60; if it does, your graphics card is working too hard and could damage itself.  Nvidia Control Panel (built in) is the first option you should try, but it doesn't always work (and never works in windowed mode), so if you can't cap the frame rates with Control Panel, you can try Nvidia Inspector (free download) instead.  Here are some screenshots of the setup; note that you'll use TS3w.exe on patch 1.67 or lower but TS3.exe (without the W) on patch 1.69:

https://forums.thesims.com/en_US/discussion/comment/16540301/#Comment_16540301

Also, please do clear the cache files.  It's perfectly safe and helps keep your game healthy; many of us delete those files after every game session.

The other thing to note is that playing in Isla Paradiso presents a variety of issues from the very beginning.  I could list them out, but the summary is that the world is so poorly made it's almost unplayable.  Those of us who would like to use it usually either modify it ourselves or download a fixed version from a world builder who was kind enough to share her work.  Since you've already played in this world with this family for a while, you might rather fix their homeworld than move them somewhere else, but either way, you're not going to be able to play in an unmodified IP without some major, even game-breaking, issues.

http://forums.thesims.com/en_US/discussion/811253/removing-ip-lag/p1

I know that this doesn't seem directly related to your travel issues, but the extra resources the game engine is spending trying to fix the route fails and other glitches in IP are resources it doesn't have to properly execute the travel transition.  There are mods to help with travel errors, and I can tell you where to find them if you're interested.  But even with the best mod intervention, IP is still hopelessly broken and will remain so until you intervene.

Cache files are cleared.

Okay, so I managed to view my fps using the control panel... and HOLY, it's jumping between 200 and 270 at increadible speed.

I didn't know Isla Paradiso was this... buggy. I noticed that I kept having lags because NPCs got stuck somewhere, but tbh I simply deleted half of the sims on the island. But as much as I'd enjoy that island-features, I'd rather restart from the beginning than continue as it is now. Could it be that my fps is going insane because of Isla Paradiso?

So I can try to fix my homeworld using the link you sent me?

If I manage to fix my homeworld but traveling still doesn't work, I'd really appreciate a mod to help me. I did find a few links while browsing through solutions but they lead to dead websites. So... yes, I'd really appreciate it.
Thank you so much for helping me and guiding me through this.

@Saddy-chin  Fps and Isla Paradiso are two completely independent issues.  Your fps is a function of your graphics card, and playing in IP doesn't make a difference.  You really do need to bring those frame rates down, no matter what world you want to play in.

As far as IP goes, you can do all the listed steps yourself if you're willing to put in the time and effort.  Or, you can just download user ciane's already fixed up version—it loads as a save, so you can start playing forward from there.  You can save your existing family to the bin (if you want to save the house too, you should probably do so separately) and then place them in a new neighborhood, whether it's the fixed version of IP or somewhere else.  Once its issues have been addressed, IP plays quite smoothly.

Side note:  You should never object-delete sims (or pets, or imaginary friends that have become animated).  Doing so only deletes their bodies; their data remains in the game and can cause corruption down the road.

For mods that will help keep your game as glitch-free as possible, you'll want NRaas ErrorTrap and Overwatch.  Combining them with Traveler fixes most of the problems associated with broken travel transitions.  If you've never used mods, I highly recommend reading about how they work before using them.  And, of course, adding third-party content to your game is not officially endorsed by EA, so use at your own risk, etc.  Also, be sure to select the correct download for ErrorTrap, as it has a different version for patch 1.69/Origin, patch 1.67/disc, and patch 1.67/Steam installs.  (The other mods will all work on both 1.67 and 1.69.)

http://nraas.wikispaces.com/How%20To%20Install

http://nraas.wikispaces.com/Where+Can+I+Find+It%3F+More+Wiki+Information+And+Help

I tried to save my family to the family bin... but it didn't work. I got the loading screen but once it was 'done' I saw my family wasn't saved. That's why I am more or less unable to leave Isla Paradiso with my family as it is. I mean... If there's no way around it, I guess I have to restart from the very beginning and recreate them in CAS. I'd rather do that than keep playing with these problems.

Well, I did save my house, at least that's something. I will get ciane's fixed version then and take a look at the other mods you recommended. I hope that will fix the travelling problem and keep others from appearing.

I'll say thanks for now and try to get the mods running.
Thank you a lot for your help.

@Saddy-chin  At the very least, the family should still be in the bin from when you originally created them in CAS.  You would have had to place them from the library into town, so unless you deleted them, they'll still be there.  (If you tried a clean folder, they'll be an entry in Library inside your old game folder.)

Even if they're not, you can bring up the cheat console (crtl-shift-c) and enter "testingcheatsenabled true" without quotes.  Then shift-click on one sim and select "Edit in Create-a-Sim."  Once in there, you should be able to save the sim to the bin (along the bottom of the screen, I think you want the ". . ." button).  So when you're ready to start a new game, you can bring up the list of premade sims, and your sims will be there for you to put back together as a family.  Sims saved this way are stored in files in your SavedSims folder.

Edit:  Maybe the problem is that you already have a family of the same name (i.e. these sims when you created them) in your library.  You can move those files out of your game folder (in Library) to see if it makes a difference.