Did you encounter a bug in SumatraPDF?
First, see if it still happens in latest pre-release version. It's possible that a bug has already been fixed there.
If yes, please create a bug report in our issue tracker.
Does it involve a specific PDF (or CHM or XPS or ...) file? Please attach it to the issue (try dragging and dropping on the issue field). Without a test document we rarely can make progress on fixing the issue.
If the file (or other information) is confidential, you can e-mail it directly to [email protected] (Krzysztof Kowalczyk, SumatraPDF's main developer).
If you report a crash, please:

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