This video will show you how to manually install install Latex packages in MikTex in Windows 10. Most packages (graphicx, float, tocloft, hyperref, etc)
Most of the packages can be downloaded from CTAN: https://ctan.org/?lang=en
You can search the package on CTAN, or just google the package, such as "float package Latex", then just hit download to get a zipped file of the Latex package.
After it downloads, right click on the package and choose the extract all option.
In the extracted folder check if there is a .sty file, this is generally what the package is looking for. If there is a .sty and no .ins, then you can directly proceed to making the folders and importing them to Latex. If there is a .ins, you will need to run Latex on it first. You can do this by clicking the browser bar at the top, and type in cmd and hit enter. In the command window that pops up, type:
Then hit enter to build the package. Some packages may require additional options in the command prompt, others need no input, or just need you to hit enter again as the one in the video does.
After the package is built, you will need to create a folder to store all the packages. It needs to have the specific format of a base folder with any name, and then a folder inside of it name tex, and then a folder inside that named latex.
After you create this folder, you can drag any packages inside the latex folder. You want the folder that has the .sty inside of it. You can right click on it to choose copy, then paste it into the folder.
The next step is to open the MikTex Settings (Admin) program, which you can find by searching MikTex. In the window that pops up, choose the Roots tab, and then hit add at the bottom. Here, search for the top folder you created (NOT the tex or latex folder), and choose it. Then hit apply at the bottom and a window should pop up and quickly and install all of the packages.
Your Latex installation should now be able to utilize those packages. If you have correctly put your packages in the folder and Latex still does not recognize them, try going back into the MikTex settings and remove and re-add the folder, and apply it again. The packages should now be available.
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