Before you pick a tool
Most document problems are one of a handful of situations wearing a different hat. These guides tell them apart, then point at the tool that fits — including the times when the obvious tool is the wrong one.
The attachment bounced, or the upload form refused the file.
Most oversized PDFs are oversized for one of three reasons, and each has a different fix. Guessing wastes a round trip with the person waiting for the file.
You need to edit or reuse text that is currently locked in a PDF.
These two tools look interchangeable and are not. Running the wrong one produces an empty document or a page of nonsense, and people usually blame the tool.
You have to share a document with something in it removed.
The most common redaction mistake leaves the original text sitting in the file underneath the mark, fully selectable. This is how documents leak.
Several files or scans need to become one document.
Merging is simple until page 10 lands between page 1 and page 2. That is almost always a sorting problem, not a tool problem.
Someone emailed a document and asked for it back, signed.
The print-sign-scan loop turns a clean file into a crooked photo of itself. Placing a signature directly keeps the original quality.
You converted a document and are about to send it on.
A converted file that opens without an error is not a converted file that is correct. Four checks catch nearly everything that goes wrong.
Go straight to the workspace. Your first eligible task finishes before you even sign in.