How to fix the module not found problem: can’t resolve when deploy nextjs but not local

Deploying the Next.JS application to hosting platforms such as railway is often a challenge, especially when everything runs smoothly at local but suddenly errors appear during the build process on the server. One of the common problems is error “Module Not Found: Cannot Complete”caused by differences in case sensitive in the file name or folder.

In this article, I will share my experience overcoming the error, complete with solutions steps that you can try.

The problem I have

Some time ago, I tried spread Next.JS Project to Railway. Local, the project runs without obstacles. However, during the process Wake up on the trainError appears like this:

Module not found: Can't resolve 'path/to/FileName'

Initially, I was confused because everything seemed fine on the local. I also tried googling to find a solution, but there was no specific answer to this problem. After some time frustrated, I found a discussion on Forum Train which gives a bright spot.

Causes of problems

This problem is caused by Case sensitive difference Between the file name or folder in the local and detected by the system on the server. For example:

• Local: FileName.js
• On the server: filename.js

Operating systems such as MacOS or Windows usually do not mind the sensitive case in the file name or folder. However, the Linux server used by hosting platforms such as railway very concerned about case sensitive. As a result, the file whose name is inconsistent becomes undetected when build.

The solution I found

To overcome this problem, you need to set the GIT to detect file changes or folders based on Case sensitive. Here are the steps:

1. Check the difference in sensitive case in GIT:

GIT by default ignores changes in case sensitive. To change it, run the following command in the terminal:

git config core.ignorecase false

2. Identification of problem files:

After running the command above, GIT will begin to detect changes in files or folders that only differ in upper and lowercase letters. Run the following command to see a list of changes:

git status

3. Improve file name or folder (If necessary)

Make sure the file name or folder is locally according to what should be, according to the correct sensitive case.

4. Commit and push Change:

After the file name is repaired, commit the change to the GIT and Push repository to the server:

git add . git commit -m "Fix case sensitive file names" git push

5. Re -build project:

Deploy your project to Railway or other platforms. If the steps above are carried out correctly, error “Module Not Found: Cannot Complete” should have been resolved.

The final result

After I followed the steps above, the error was resolved, and my application can be deployed without problems. The build is finished smoothly, and the application can be accessed as it should.

Conclusion

Problems like this may not only occur in the railway, but also on other hosting platforms that use the Linux server. Therefore, it is important to ensure the name of the file or folder is consistent with the correct sensitive case.

By running simple commands like git config core.ignorecase falseYou can avoid confusion and improve errors caused by differences in case sensitive.

Hopefully this article is useful and helps those of you who are facing similar problems. If you have other questions or experiences, don’t hesitate to share in the comments column!