Mac users read here. (Sorry Mac users, I don't own a Mac and have no screenshots to share. The link is helpful, though.)
Windows 7 & Vista users can watch a YouTube video on installing GIMP scripts here. (Note: Plugins - [*.exe and *.py files] are saved the same exact way, except they go in the "plug-ins" folder)
XP Users (especially those using Internet Explorer as a browser) click here.
Linux users read here. Also a few Ubuntu screenshots of GIMP Edit/Preferences/Folders (the correct folders for plug-ins and scripts are shown here):
Plug-ins
Scripts
At one point, I found myself on the GIMP Registry not knowing a thing about how to install scripts or plug-ins. The fundamentals of how this is done is documented on the GIMP.org site, located here. But before you go running off to check out that link for the information you desperately crave, stick around and view the screenshot instructions I'm posting below:
So you're browsing the GIMP Registry and you find a script or plug-in that sounds interesting and you want to try it. No problem.
If it's a .scm file, right click the actual link and choose "Save Link As". You'll see this prompt below:
Now you'll need to browse in explorer to save it to the right place. Since it's a *.scm file it needs to go in GIMP's script folder, as shown below (Vista):
IMPORTANT:
In Windows Vista, the path to the GIMP scripts folder is C:\Users\Your User Name\.gimp-2.6\scripts. In Windows XP, the path is C:\Documents & Settings\Your User Name\.gimp-2.6\scripts.
NOTE:
The path for plug-ins are at the same location but instead of the scripts folder, you put the plug-ins in the "plug-ins" folder.
Notice that the plug-ins folder is directly above the scripts folder.
Plugins or scripts that come in a zipped file have to be handled differently, because you want to extract the files from the zipped file into the appropriate folders as shown above. Simply double-click the zipped file to extract them.
For adding new scripts, all that is required is that you refresh the scripts under Filters – Script-Fu – Refresh scripts. Adding new plug-ins, however, require that GIMP be closed and restarted. For most plug-ins, the most obvious place to find them is in the Filters menu, unless the Plug-in author instructs otherwise.
Scripts on the other hand are a little more tricky to find if the information on the GIMP Registry is lacking. One trick to finding where scripts are listed in the menus, is to open it and check out the register, located toward the bottom of the script file:
Sure enough, this script can be found under Filters – Light and Shadow, as indicated on the last line above.
Python plug-ins can be opened with an editor, but DO NOT OPEN executable plug-ins with an editor (e.g. someplugin.exe). If you cannot find a plug-in location in the menus, go to the Plug-in Browser under Help on your GIMP menu bar. (Thanks Saul!)
Most importantly, READ THE POSTS AND COMMENTS for the script or plug-in you are planning to use BEFORE you download it, and make a note of special instructions for the handling of that particular script or plug-in. Print it out, if you have to.
If all else fails, direct your comments to the author of the plug-in/script for logging errors and asking for additional instructions. The best way to get help is to clearly define your problem, including any error messages, and be specific about the problem. Don't post new comments on a new forum subject that read like this : "It's not working! HELP HELP HELP!" That fails to explain anything to anyone, and it's downright lazy and rude. Instead, run a checklist in your comments, that explain, that you downloaded the file correctly, it's in the right folder as indicated in the instructions. Specify your operating system and version of Gimp (i.e., using Vista 32 bit, GIMP 2.6.7) List error messages verbatim, and if it has a number assigned to it, include it.
We were all noobs at one point or another, so it's understandable that people are going to need a little extra help in getting started. The best thing you can do to help others help you, is be as helpful as you can, yourself.
FINALLY:
If you use Notepad to save *.scm files, pay close attention to what you are saving it as, and where you are saving it to:
See the "Save as type:" showing Text Documents (*.txt)? That needs to be changed to "All Types"
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03:59, 16.01.2010
"If you cannot find a plug-in location in the menus, leave a comment with the author and ask, always."
It would be quicker and easier to search for the script/plug-in using the Plug-in Browser under the Help menu.
05:21, 16.01.2010
Thanks Saul! :) I’ve added your suggestion in place of that comment.
16:25, 20.01.2010
Hello i seem to be having a problem with putting in a plugin from here http://registry.gimp.org/taxonomy/term/123
I am using windows vista 64-bit and gimp 2.6 as the folders that have all the info in it and gimp 2 as the starting of the program. I have no Scripts file by the plugin file all i have is a plugin file and when i access that i see script fu and theres a scripts folder in there but when i put in the .scm file in that it didnt work. Then i put the other file just in the plugin folder. I dont know if it has to be more than 1 file for this because i saw a bunch of other files for the other plugins that it has but when i downloaded this plugin i only got 1 file.
17:30, 20.01.2010
Your comment is puzzling. If you followed the instructions as indicated (as to which file type goes in which folder) you wouldn't have had any problems. But since you said plug-in, that would indicate the python file (extension *.py) which means you need to have Python installed on your computer and GIMP must recognize that Python is installed. (See this link: http://www.gimpusers.com/tutorials/install-python-for-gimp-2-6-windows.html).
Another point: I rarely ever place ANY of my scripts (*.scm files) in c:\Program Files\Gimp 2.0\ folders. The reason for that is, if I upgrade GIMP at any time in the future, my scripts could be affected by the upgrade).
Install your scripts (.scm files) in your USERS/YOUR USERNAME/.gimp-2.6/scripts folder. Then REFRESH your scripts in Filters/Script-fu menu option in GIMP. Once you do that, the script should be showing up in Script-Fu/Layer Effects on the GIMP menu bar.
There should only be ONE .scm file and only ONE .py file (depending on which option you chose to install).
06:53, 29.01.2010
Thanks a lot for this. Now, I know how to get scripts working. Thanks again.
15:44, 04.02.2010
I just uninstalled gimp and got the same one i got above on the same comp. but before installing it i got python 2.6.4 and the gtk bundle like the installer asked for but when i installed it again it still would not allow me to click on the box to have python scirpting so i just installed it without it anyways..
and i have no clue where that file loacation to put .scm files is at…..
15:48, 04.02.2010
ok nvm i did find it out… Make SURE you are puttin the .scm or python scirpting in the program files folder not the desktop one lol. and now it works for me thanks you site helped alot when other sites just said do this and this but where using something else.
18:57, 04.02.2010
Arkamond:
I put my .scm files and .py files in my C:\Users\my_username\.gimp-2.6\ folders, not the program files folder. I specifically explained why in the post. If you start installing all your scripts and plug-ins in the Program Files Gimp folders, you better keep them backed up, because when you go to install a new version of GIMP later on in the future, there is a good chance those files will get uninstalled. The whole reason for the Users .gimp-2.6 folders is keep GIMP files isolated and out of harm's way.
No idea why you would have .scm files on your desktop unless you saved it there.
.scm files = scripts folder
.py and .exe = plug-ins folder
It's that simple.
22:43, 25.03.2010
Thanks! I tried it once and it worked immediately. That was soooo easy.
06:32, 22.04.2010
I noticed the link to logarithmic.net/pfh/resynthesizer points to a zip file with the script/plugin. This is apparently a workalike for PhotoshopContentAware Scale and Fill. It appears that the zip file's internal files have directory paths. Does this mean that the zip file should be placed in the application folder and then extracted? or what? There are ~17 files, each with a slightly different path. Where in the GIMP application folder should I place it? Because an experimental extraction to a dummy folder shows that the zip will place files in both the script and the plugin folders at different levels. There are no instructions from the author(Harrison). I hope the above makes sense, and thanks for any help you can offer.
12:02, 22.04.2010
There are only 3 files, I’m aware of, that are needed for a Windows OS. I haven’t set resynthesizer up for a linux/debian system.
For Windows, resysnth.exe or resynthesizer.exe (depending on which version you are using) goes into the .gimp-2.6/plug-ins folder. There are two .scm files, smart-remove.scm and smart-enlarge.scm. Both of these files go in the .gimp-2.6/scripts folder.
If you’re on a linux system, you might want to ask the proper install for resynthesizer at registry.gimp.org.