Error 404 or 500 when downloading large static JSON file in IIS 7

Question

What I wanted to do was fairly simple you would think. Create static json file so browsers can cache output and you don't have to poll the database for large chunks of data.

So I created a JSON file test.json with the content [{"frut":1}] (My actual files are in the region of 3mb)

I went to http://domain.com/frut.json and I got an error 404

404 - File or directory not found.
The resource you are looking for might have been removed, had its name changed, or is temporarily unavailable.

First of all I was suprised.. the file was there, why not offer it for download or a 403 forbidden...

Okay. Google, end up at https://www.sencha.com/forum/showthread.php?33266-Some-Problem-with-JSON/page2#post_229858

So I tried

IIS7 configuration to support JSON:  
Using IIS manager: clock on IIS server (the main node on the left - where you see the machine name)  
1. Add ‘json’ MIME Type   
    * Double click on ‘MIME Types’ icon  
    * Click ‘Add…’ link (under Actions section on the right side)  
                   In ‘Add MIMI Type’ window type:  
                   File name extension: .json   
                   MIME type: application/x-javascript  
    * Click OK, You should see the .json MIME Type added to the list of the MIME Types list.
2. Add Script Map Handler for ‘json’ MIME Type
    * Double click on ‘Handler Mappings’ icon
    * Click on ‘Add Script Map…’ link (under Actions section on the right side)
    * In ‘Add Script Map’ window type:
           Request path: *.json
           Executable: C:\Windows\System32\inetsrv\asp.dll
           Name: JSON
    * Click OK (Message box pops up with a message: Do you want to allow this ISAPI extension?...etc ) Click Yes, You should see the .json extension added to the list of the Handler Mappings list

Okay. Error 500 instead of error 404. Not understanding why... how, what on earth is going on. I checked logs. nothing there. Just a vague mention of 500 on a request. that's it. no details, no error logs. nothing.

I'm at this point seriously starting to hate microsoft again.

Read a lot about request limits, but that's not it becuase this file doesn't even reach 1kb, let alone the 2gb limit.

Google more, end up with nothing to show for it.

The question How do I get a simple JSON text file to show up in IIS 7.5 so I can request with an an ajax request without IIS killing itself over a simple text file.

The answer is http://serverfault.com/questions/39989/iis-cant-serve-certain-file-extension#497285, if anyone is feeling like answering it, go ahead, otherwise i'll self answer this. This question is mainly for future googlers who are banging their head on the desk because of IIS — Tschallacka, Dec 11 '15 at 10:39

Tschallacka · Accepted Answer · 2018-04-24T19:07:38.410

The solution seems simple but is nigh impossible to find to get the desired behaviour out of IIS.

The solution is basically, don't serve as application/x-javascript but as text/json

Based on the answer at IIS Can't Serve Certain File Extension

Using IIS manager: click on IIS server (the main node on the left - where you see the machine name)

Add json MIME Type
- Double click on MIME Types icon
- Click Add… link (under Actions section on the right side)
  
  In Add MIME Type window type:
  File name extension: .json
  MIME type: text/json
- Click OK, You should see the .json MIME Type added to the list of the MIME Types list.

Now when you request the file it serve it as a regular text file, just the way you want it.

Error 404 or 500 when downloading large static JSON file in IIS 7

1 Answers1