Troubleshooting guide: ReSharper reports "Cannot resolve symbol" error

Problem

This is an article with common symptoms and possible workarounds we can suggest if ReSharper reports an error "Cannot resolve symbol".

Resolution

Look at the following tips one by one if the problem is in the C# file:

• use ReSharper | R# Out-of-Process | Repair Out-of-Process mode
• update ReSharper to the latest version;
• clear caches using ReSharper | Options | Environment | General | Clear caches;
• check where the error is coming from: from ReSharper or Visual Studio. To do this, try turning off ReSharper using Tools | Options | ReSharper | Suspend Now. If disabling ReSharper didn't help, then the error is coming from Visual Studio. If it helped, then it's coming from ReSharper, try the following steps.
• [for versions prior to 2026.2] disable the Read solution model directly from project/solution files in ReSharper | Options | Environment | General and check if it makes any difference. If disabling the option above helps, then we need additional information and a sample solution to investigate the issue.
• if disabling the option Read solution model directly from project/solution files does not help, and there is still red code in the editor, then collect a log file.

If you see red code in C++ files in the editor but the project is compiled successfully:

1. in the file with unresolved symbols or #include files, invoke ReSharper | Navigate | Go to Action;
2. type /all Dump C++ inclusion context and press Enter;
3. save the resulting dump file.