You may have already known about the convenient feature of WinEdit LaTex environment that allows you to jump from the generated PDF line, when clicking that line, back to the corresponding tex source line in the WinEdit editor window. This is immensely helpful and conducive to efficient Tex editing and revising.
However, somehow you may find that the feature suddenly fails to work. That happens to me recently, making a lot of headaches when fiddling with how to fix it and bring the nice feature back to work.
Regardless of how other online posts complicated this solution, here is the quick steps:
1. Download Sumatra PDF reader and install it (to avoid unnecessary trouble, just install it to the default folder, for instance 'C:\Program Files (x86)").
2. Open your WinEdit and get into 'Options' (from the main menu) -> 'Execution Modes'
3. In 'PDF Viewer' tab, set Sumatra PDF reader (the executable SumatraPDF.exe) as the 'PDF Viewer Executable'; leave 'Use --synctex switch when --src is enabled' unchecked; fill '--synctex=1' in SyncTex switch box
4. Move to the 'Console Applications' tab, choose 'PDFTexify' in the navigation menu on the left-hand side, fill '--pdf --tex-option=--synctex=-1' in the 'Switches' box.
5. Ctrl+Shift+'P' (or choose 'PDFTexify' from the 'Tex'->'PDF' menu items) to build your PDF; save settings and get back to your editing environment.
6. Now try to double click a line in the PDF, the beautiful functionality should play like a charm!