Visual Studio can't 'see' my included header files

Question

I created an empty \'Demo\' project in Visual Studio 2008 and added some existing projects to my solution. Included \"MyHeader.h\" (other project\'s header) in main.cpp file

Answer 1

If it is the case that only the IDE indicates that it cannot find included files, but compiling is successful, the issue is simply that IntelliSense is not fully up to date with recent changes. This can happen specifically when including existing projects, in my own experience. Deleting the .sdf file (= IntelliSense database) that is generated in your solution directory forces Visual Studio to regenerate it, so that it is up to date again. Just doing a "clean" will probably do the same thing, but takes more time since everything will be generated again then.

Answer 2

Delete the .sdf file that is in your solution directory. It's just the Intellisense database, and Visual Studio will recreate it the next time you open that solution. This db can get corrupted and cause the IDE to not be able to find things, and since the compiler generates this information for itself on the fly, it wouldn't be affected.

Answer 3

I know this is an older question, but none of the above answers worked for me. In my case, the issue turned out to be that I had absolute include paths but without drive letters. Compilation was fine, but Visual Studio couldn't find an include file when I right-clicked and tried to open it. Adding the drive letters to my include paths corrected the problem.

I would never recommend hard-coding drive letters in any aspect of your project files; either use relative paths, macros, environment variables, or some mix of the tree for any permanent situation. However, in this case, I'm working in some temporary projects where absolute paths were necessary in the short term. Not being able to right-click to open the files was extremely frustrating, and hopefully this will help others.

Answer 4

This happened to me just now, after shutting down and restarting the computer. Eventually I realised that the architecture had somehow been changed to ARM from x64.

Answer 5

If the visual studio says that you miss some file in the current source file folder, there is one solution that i used. Just right click the file you want to add and choose Open Document, if it really doesn't exist, then you should see something like cannot find file in the source file path = "somewhere in your computer", then what you could do is the add your source file into that path first and see if it works.

Answer 6

I encountered this issue, but the solutions provided didn't directly help me, so I'm sharing how I got myself into a similar situation and temporarily resolved it.

I created a new project within an existing solution and copy & pasted the Header and CPP file from another project within that solution that I needed to include in my new project through the IDE. Intellisense displayed an error suggesting it could not resolve the reference to the header file and compiling the code failed with the same error too.

After reading the posts here, I checked the project folder with Windows File Explorer and only the main.cpp file was found. For some reason, my copy and paste of the header file and CPP file were just a reference? (I assume) and did not physically copy the file into the new project file.

I deleted the files from the Project view within Visual Studio and I used File Explorer to copy the files that I needed to the project folder/directory. I then referenced the other solutions posted here to "include files in project" by showing all files and this resolved the problem.

It boiled down to the files not being physically in the Project folder/directory even though they were shown correctly within the IDE.

Please Note I understand duplicating code is not best practice and my situation is purely a learning/hobby project. It's probably in my best interest and anyone else who ended up in a similar situation to use the IDE/project/Solution setup correctly when reusing code from other projects - I'm still learning and I'll figure this out one day!