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net::ERR_FILE_NOT_FOUND, no typos and files are in the same directory

I have an index.html file with <script src=”sc2.js”></script> in the head section. In the same directory I have file sc2.js that has some really simple JavaScript code I wanted to test to see what it prints. The html displays correctly in my browser, but the console says:
index.html:8 GET file:///Users/myname/projectfile/%E2%80%9Dsc2.js%E2%80%9D net::ERR_FILE_NOT_FOUND
Am I missing something to make it possible to run the code in my browser? I can still run old JavaScript projects in the browser with no problems. I also tried to move the script tag around and add the full path, which made no difference. The code works in jsfiddle.net. I'm using Chrome Canary.

javascript stopped working but works on diffrent server

I need your help with a strange problem.
The company I work for has a company website.
I have been updating pages on their website the last couple of days.
After updating, I decided to upload the website,
but suddenly the javascript doesn't work anymore.
I get the following error when I press f12
Uncaught SyntaxError: Invalid or unexpected token
base.js:1 Uncaught ReferenceError: $ is not defined
at base.js:1
On the test server (my own server) it works without any problems.
On the main server (company server) it doesn't work.
What could be the issue for this?
It's not on just one page, it's on every single page that the Javascript doesn't work.
[update]
I know about the different versions of Javascript.
This is already fixed in the testing environment of the company website.
This still doesn't fix the current problem.
Thank you
Wesley

On the test site you use jQuery 3.3.1:
<script src="js/jquery-3.3.1.min.js" type="text/javascript"></script>
On the main site you use jQuery 1.10.1:
<script src="https://www.aska-ltd.jp/js/jquery-1.10.1.min.js"></script>
Please both use v3 if you don't have specific needs.

It looks like you are using jQuery for your JavaScript code.
The header of the first page contains a tag for loading jQuery:
<script src="js/jquery-3.3.1.min.js" type="text/javascript"></script>
But on the second page, you never load jQuery.
As I don't know how the file structure of your server is, I cannot tell you the exact path, but you need to make sure you load jQuery in a similar way on your company website.
EDIT:
I noticed that you load jQuery from https://www.aska-ltd.jp/js/jquery-1.10.1.min.js. However, this file is not the original file (compared to https://code.jquery.com/jquery-1.10.1.min.js using MD5). If you want to use this old version (not recommended), you can try to re-download it or simply load jQuery in its latest version from its official server (recommended).

As #NoobTW and #SapuSeven have said, there is an error in the jQuery script on the production site.
On the production site, try replacing this <script src="https://www.aska-ltd.jp/js/jquery-1.10.1.min.js"></script>
with this <script language="JavaScript" type="text/javascript" src="js/jquery-3.3.1.min.js"></script>
Also, if you load jQuery from a CDN, it may help simplify things. Here is one option for jQuery 3: <script
src="https://code.jquery.com/jquery-3.3.1.slim.min.js"
integrity="sha256-3edrmyuQ0w65f8gfBsqowzjJe2iM6n0nKciPUp8y+7E="
crossorigin="anonymous"></script>
See here for more options: https://code.jquery.com/

JQuery never loads at all on the main server. I tried taking the code from the file on the server and evaluating it, but discovered some sort of corruption in the JQuery file your server is returning:
If the same thing happens with an updated version of JQuery, check whether it’s also corrupted. It may be some sort of transformation the server is incorrectly performing.

Uncaught SyntaxError: Unexpected token < on each js file that invoked in the index html

I am using mean stack to build a website, when testing, chrome returns the error like:
Uncaught SyntaxError: Unexpected token < angular.js:1.
I don't know what's wrong and what should i do.
Here is the directory of my app:
E-study
-client
-app
-components
-all the libraries are here.
-index.html
-controllers.js
-node_modules
-server
-config
-server.js
And I run the server in E-study like :node server/config/server.js
The scripts in the index.html is<script src="client/components/angular/angular.js"></script>
Just don't know why all the js files are changed to index.html when open in the browser.

open up those library files and see if there are some extra symbol < probably you will find it in the beginning.. if still not able to fix... simply download the fresh library (if those are libraries) from the internet and try again.
make sure that you don't put <script> </script> tags in the included .js files. that is an incorrect syntax for script files.
also make sure you are providing the correct path??? providing incorrect path can return a builtin customized error page. which is html. may be that is the source of error because returned page is HTML which is most likely going to start with a < symbol. and offcourse not a js file.
to ensure that the incorrect path is the issue just copy the path you included in the code and and paste into your favorite browsers url bar and hit enter. if you are not getting the script in plain text.. then it means you are not providing the correct path.
and if it is return a customized error page like .. 404 not found then probably it is returning the html and this is where the error is coming from.

In external js files, which you refer in some other files, don't use <script>..</script> tag.

For express server try to set the static path to entire project folder.It worked for me
app.use(express.static(__dirname ));

Could be a ReCaptcha bot checker type thing intercepting requests for JS files and serving up an HTML page instead, which is invalid HTML so it throws the < is invalid message error.
I know siteground specifically has issues with this intercepting CDN routed traffic.
Check with the host to remove this issue, in this case it's their anti-bot security setup. This has remedied these issues with Siteground for me.

Qtip2 loads a "jquery.qtip.min.map" from internet and slows down site

I included Qtip2 on my site and used the following snippets while the files are hosted on my own server as mentioned here:
<!-- jQuery FIRST i.e. before qTip (and all other scripts too usually) -->
<script type="text/javascript" src="/scripts/jquery.min.js"></script>
<!-- Include either the minifed or production version, NOT both!! -->
<script type="text/javascript" src="/scripts/jquery.qtip.js"></script>
Though hosted on the same server as the website the script loads the following additional file from the CDN of Qtip2:
https://cdnjs.cloudflare.com/ajax/libs/qtip2/2.2.0/jquery.qtip.min.map
This slows down my side extremely:
I could not find any information about this. Any idea how to avoid (if not necessary) or replace and host on my own server?

The final line of the Qtip2 script is a line lke this:
//# sourceMappingURL=http://cdnjs.cloudflare.com/.../jquery.qtip.min.map
Unfortunately the URL currently returns a 404. If you're hosting Qtip2 yourself, you should be able to find and remove that line at the end of the script. Otherwise, don't worry too much because the .map file is only requested when Developer Tools is open. Normal visitors won't download it.
Here's more info on .map files: jQuery's jquery-1.10.2.min.map is triggering a 404 (Not Found)

The *.map file is a source map. It contains informations like function positions of the non-minified source code of Qtip2. Notice that I used the minified version of it on my webpage.
Source maps help to develop with a postprocessed (e.g. minified) source code without losing the ability to look into the code, for example when errors occur.
The chrome debugger as you can see on the image in my question above downloads it by default. After disabling that function in the debugger settings the file won't be downloaded any longer.
Take a look at this video for a short information or this documentation from Google.
Firefox offers the same feature as you can see here.

I have downloaded this plugin from here and the problem is solved!
http://qtip2.com/v/2.2.1/

jquery.js call from HTML syntax error

I have an HTML page generated by an objective-C application and I want to load and open it in a local directory (not in a web server). The javascripts jquery.js and jquery.plot.js are stored in the same directory before the page is loaded.
I made the HTML page by following closely the examples available on http://flot.googlecode.com/
The scripts are declared in the HTML page as follows :
<script src="jquery.js" language="javascript" type="text/javascript"></script>
<script src="jquery.flot.pack.js" language="javascript" type="text/javascript"></script>
When I open the page, the expected graph (generated by the scripts) doesn't show up and I have the following syntax error in the javascript console :
Uncaught SyntaxError: Unexpected token ILLEGAL
The script source in the javascript console is made of strange (chinese ?) ideograms which are obviously "unexpected token" if it is what the browser sees.
I have the same problem with Chrome, Firefox and Safari.
The problem is not systematic because sometimes, it works !.
I have made tests with files prepared manually and again it works sometimes only.
I have also copied the same file which didn't work in another directory where the jquery scripts were present and, surprise, it worked ! but not always...
I have exhausted all my ideas on this problem and your help will be very much appreciated

Did you copy the JavaScript from an external source? I know I have had problems when copying from JSFiddle for example. Try removing any whitespace and see if that will get rid of the illegal token error.

I just had this problem and it was because the server on which my javascript was being hosted wasn't configured to send the javascript file with the correct MIME type. See this question.
Instead of fixing my server, I just opted to use a CDN path from cdnjs.com:
//cdnjs.cloudflare.com/ajax/libs/flot/0.7/jquery.flot.min.js