I am using the 2019 version, and lately, it has been taking a long time to start Trados or to open files and projects, if I close a project, or open it, I need to waite minutes to start the next stepl like to open the project file, or to create a return package.
A reset might help you with this. To do this just close Trados Studio and then delete these folders:
%appdata%\Trados\Trados Studio\Studio15\
%appdata%\Trados\Trados Studio\15\
You will lose your plugins, and also your settings, but your projects and other resources will remain untouched. Putting the plugins back is trivial via the integrated appstore.
If you can't find these folders then you need to unhide your hidden files/folders:
Then restart Trados Studio and see if that helped.
Kind regards,
Ana Sabo | RWS Group
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Hi Ana,
Thank you for your help, but was not able to find those folders.
Copy and paste the path provided above: C:\Users\%USERNAME%\AppData\Roaming\SDL\SDL Trados Studio\15.0.0.0
to the address bar of your Windows Explorer and press the Enter key. It should work.
I did, the folders do not have these files 
I checked all the folders and they are empty, only the files shown in the screenshots appear there. I have already unhidden the hidden folders.
Please stop confirming the replies you get as verified answers. When you do that, the thread shows up as having been answered satisfactorily when in fact you are still trying to solve this.
Also, the images you provide are very difficult to use and in fact I cannot access them at all. All you need to do is copy/paste an image into your reply. Then we can see the image without having to click on some link that doesn't work.
You could also try pasting the path to the files you have found? That might help us understand where you're looking. It is impossible for these folders not to be there if you have Trados Studio running on your computer.
Paul Filkin | RWS
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Sorry about confirming the replies, it was by mistake, here is the link I am checking C:\Users\%username%\AppData\Roaming\SDL\SDL Trados Studio\15.0.0.0
Here is the images 
So you can see them. Go back up a level to SDLTradosStudio where you see the folders themselves and not just what’s inside them and you’ll be able to delete them.
Paul Filkin | RWS
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I was trying from few days, and I was not able to find these files:
%appdata%\Trados\Trados Studio\Studio15\
%appdata%\Trados\Trados Studio\15\
You just showed screenshots of these folders. Perhaps there is some confusion here and you are showing what you were asked to find and not what you actually find. Let me try and help explain this. First of all, these would be wrong because they are pretty old and we didn't use "Trados" on its own back then:
%appdata%\Trados\Trados Studio\Studio15\
%appdata%\Trados\Trados Studio\15\
You should be looking for these:
%appdata%\SDL\SDL Trados Studio\15.0.0.0\
%appdata%\SDL\SDL Trados Studio\15\
Find them like this:
Translate
%appdata% and press Enter - this opens your AppData\Roaming folder.If you still cannot find them please provide a screenshot showing the location YOU HAVE LOOKED.
Paul Filkin | RWS
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So, I need to remove 15.0.0.0 and a 15 folders?
Yes… that was the advice that “might” help. It’s certainly worth trying to get a fresh start. But many things can cause performance issues. Could be related to where your files are being saved and their availability… everyone uses cloud synchs for everything these days and that alone can add a performance hit… especially if you have e poor connectivity. Could be related to an aggressive setting on your security software… everyone has them these days and I reckon most users never make any changes to the defaults or understand how their solution works.
But start with the refresh… can’t hurt.
Paul Filkin | RWS
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Yes… that was the advice that “might” help. It’s certainly worth trying to get a fresh start. But many things can cause performance issues. Could be related to where your files are being saved and their availability… everyone uses cloud synchs for everything these days and that alone can add a performance hit… especially if you have e poor connectivity. Could be related to an aggressive setting on your security software… everyone has them these days and I reckon most users never make any changes to the defaults or understand how their solution works.
But start with the refresh… can’t hurt.
Paul Filkin | RWS
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You've done the courses and still need to go a little further, or still not clear?
Tell us what you need in our Community Solutions Hub