SumatraPDF Annotation Colors Not Sticking: How to Fix Defaults

You change a highlight, underline, squiggly underline, strikeout, or text annotation color in SumatraPDF, but the next annotation still appears in the old color. This usually happens because changing one annotation does not automatically change the default for future annotations, the advanced settings were not saved correctly, or Windows is opening a different SumatraPDF installation than the one you configured. Portable-folder permissions and unsupported document formats can also create confusing results.

This guide focuses specifically on default annotation colors. It does not cover interface theme colors, page colors, selection colors, or search-result highlighting. Work through the checks in order and stop as soon as one newly created annotation uses the intended color.

1. Confirm the Symptom With One Simple Test

Before editing configuration files, confirm whether the problem affects existing annotations, future annotations, or both. These are different behaviors and require different fixes.

1.1 Test a new annotation in a simple PDF

Open a small, writable PDF that you are allowed to modify. A locally stored test PDF is preferable because it removes network synchronization, browser downloads, cloud placeholders, and document-management tools from the test.

1. Open the test PDF in SumatraPDF.
2. Create one new highlight, underline, squiggly underline, strikeout, or free-text annotation.
3. Change that individual annotation to a distinctive color.
4. Create another annotation of the same type.
5. Check whether the second annotation inherits the new color or uses the previous default.

If the first annotation changes but the second one uses the old color, annotation editing is working. The unresolved issue is the default for future annotations. Continue to the advanced-settings checks below.

If the first annotation cannot be changed at all, confirm that you are working with a PDF and that the file is writable. SumatraPDF can read many formats, including eBooks, comics, CHM, DjVu, XPS, and images, but that does not mean each format supports PDF-style annotations.

1.2 Understand existing versus future annotations

Default color settings normally control annotations created after the setting takes effect. They are not a batch recoloring command for annotations already stored in a PDF.

• Existing annotation: Retains the color saved in its annotation properties unless you edit it directly.
• Future annotation: Uses the configured default for that annotation type.
• Different annotation type: Uses its own default, even if another type was configured successfully.

For example, changing HighlightColor should not be expected to change the default underline or strikeout color. Success means one new annotation of the tested type uses the intended color. Once that happens, stop changing unrelated settings.

2. Check the Annotation Defaults in Advanced Settings

SumatraPDF stores configurable defaults in its advanced settings. The relevant area is the Annotations section, not the theme, fixed-page background, selection, or search settings.

2.1 Open the correct settings file

In SumatraPDF, use the application menu to open Settings and then Advanced Options. This is safer than searching the drive for a file with a similar name because it opens the settings file associated with that running copy of SumatraPDF.

Look for an Annotations section containing annotation-specific color entries. The relevant setting names are:

• HighlightColor for text highlights
• UnderlineColor for straight underlines
• SquigglyColor for squiggly underlines
• StrikeOutColor for strikeout annotations
• FreeTextColor for free-text annotations

Edit only the entry that corresponds to the tool you are testing. If highlights are wrong but underlines are correct, start with HighlightColor rather than changing every color at once.

2.2 Preserve the settings syntax

The advanced settings file uses a structured text format. Keep each color entry inside the Annotations block, retain the equals sign, and avoid adding quotation marks, commas, or JSON-style punctuation. A representative structure looks like this:

Annotations [
    HighlightColor = #ffff00
    UnderlineColor = #00ff00
    SquigglyColor = #ff00ff
    StrikeOutColor = #ff0000
    FreeTextColor = #000000
]

The values above are examples, not required choices. Use valid color values accepted by the SumatraPDF settings format. Keep the leading # when entering a six-digit hexadecimal RGB value.

Save the file as plain text. Do not rename it, append .txt a second time, or save it as a rich-text document. If your editor displays a Save As dialog, verify that it is writing back to the same SumatraPDF-settings.txt file.

2.3 Restart and test only one new annotation

After saving, close all SumatraPDF windows. Reopen the same application, load the test PDF, and create one new annotation of the configured type. Restarting removes uncertainty about whether the running process has reloaded the edited defaults.

Success means the newly created annotation uses the chosen default. An older annotation remaining unchanged is normal. If the new annotation is correct, do not reinstall SumatraPDF or delete additional settings.

3. Check the Executable, File Association, and Document

If the advanced setting looks correct but has no effect, determine whether Windows is launching the same SumatraPDF copy whose settings you edited.

3.1 Verify installed versus portable mode

It is possible to have an installed copy of SumatraPDF and a portable copy in a downloads, tools, or USB folder. Each may read settings from a different location. Editing the portable settings file will not necessarily change the installed application launched by a PDF file association.

1. Open SumatraPDF directly from the executable you intend to use.
2. From that running window, open Settings and Advanced Options.
3. Confirm that your annotation color appears in the file that opens.
4. Open the test PDF from inside that same SumatraPDF window.
5. Create one new annotation.

If this works, but double-clicking a PDF does not, the Windows file association or a shortcut is likely launching another executable. Point the PDF association and your shortcuts to the intended copy. File association does not alter colors by itself. It matters because it can select a different executable and settings profile.

3.2 Check portable-folder permissions

A portable copy may keep its settings beside the executable. If that folder is read-only or located in a protected directory, SumatraPDF or the text editor may be unable to save the configuration.

Close SumatraPDF, edit the color through Advanced Options, save the file, and reopen it immediately. If the value reverted before SumatraPDF restarted, the editor did not save the file successfully. If the value reverts only after running SumatraPDF, the application may be unable to preserve settings or another process may be replacing the file.

For a controlled test, place the portable application in a normal user-writable folder rather than a protected system directory. Do not weaken system-wide permissions. Success means the edited value remains in the settings file after SumatraPDF closes and reopens.

3.3 Confirm the source document is appropriate

Test with a normal local PDF before blaming rendering components. A document opened from an email cache, browser temporary folder, read-only network share, or synchronized location may not behave like a local writable file.

Document permissions can also restrict modifications. Respect those restrictions rather than attempting to remove or bypass them. If annotations are prohibited, use a document you own or have permission to annotate for the test.

Codecs, Ghostscript, and printer drivers are generally not relevant when the narrow symptom is that a newly created PDF annotation uses the old default color. Investigate those components only if the actual problem involves opening a particular format, rendering PostScript-related content, or printing. They do not normally control SumatraPDF's annotation default entries.

4. Inspect or Reset SumatraPDF-settings.txt Safely

If the annotation value will not persist, inspect the settings file without immediately deleting your entire configuration. A malformed block, duplicate entry, wrong file, or unsaved change is more likely than a damaged SumatraPDF installation.

4.1 Back up the current settings

1. Close every SumatraPDF window.
2. Locate the settings file by opening Advanced Options first and noting the file being edited.
3. Copy SumatraPDF-settings.txt to a safe backup location.
4. Give the backup a clear name such as SumatraPDF-settings-backup.txt.

This preserves preferences such as display choices, remembered files, and other customizations. Do not publish the file without reviewing it because application settings can contain local paths or history information.

4.2 Look for structural problems

Within the settings file, verify that the five color names are inside the Annotations section. Check for accidental quotation marks, missing equals signs, malformed brackets, or duplicate blocks introduced during manual editing.

If you copied a configuration fragment from a forum or an old backup, compare it with the structure generated by your installed SumatraPDF copy. Do not assume that an unrelated example matches your configuration. Preserve setting names exactly, including capitalization.

Save the corrected file, restart SumatraPDF, and create one new annotation. If it uses the correct color, the settings parser is reading the block successfully.

4.3 Perform a reversible settings reset

If you cannot identify the malformed entry, use a reversible reset rather than permanently deleting the file.

1. Close SumatraPDF completely.
2. Keep the backup created earlier.
3. Rename the active settings file so SumatraPDF cannot load it under its normal name.
4. Start SumatraPDF and allow it to create or use clean defaults.
5. Open Advanced Options and configure one annotation color.
6. Restart SumatraPDF and test one new annotation in the local PDF.

If the clean configuration works, the old settings file contained the conflict. Reapply only the customizations you need instead of restoring the entire problematic file. If the clean configuration also fails, continue with the temporary executable test.

5. Run a Clean Temporary Test Before Reinstalling

Reinstalling is often unnecessary because application settings can survive a reinstall or remain associated with another executable. A clean temporary test gives more useful information.

5.1 Use an isolated writable location

Obtain SumatraPDF only from its official distribution source. Place a portable copy in a new folder under your user account where you have normal write access. Do not mix it with the existing portable folder or copy the old settings file into it.

1. Launch the temporary copy directly.
2. Open its Advanced Options from within that copy.
3. Set one annotation default, such as HighlightColor.
4. Save the settings file and close every window of that copy.
5. Launch the same executable again.
6. Open the local test PDF and create one new highlight.

If the temporary copy works, the SumatraPDF annotation feature is functioning. The original problem is most likely the old settings file, folder permissions, a shortcut, or Windows opening a different installation. Keep troubleshooting those items rather than changing document-rendering or printer components.

If the isolated copy fails with one ordinary local PDF, verify the exact annotation type and settings entry again. You can then consult the official SumatraPDF documentation or issue tracker with a concise report that includes the test format, the relevant settings block, whether the copy is portable, and whether the value survives a restart.

6. Quick Fix Checklist

• Test with one ordinary, writable PDF stored locally.
• Confirm the problem affects new annotations, not only existing ones.
• Open Advanced Options from the SumatraPDF copy currently running.
• Edit the matching entry inside the Annotations section.
• Use HighlightColor, UnderlineColor, SquigglyColor, StrikeOutColor, or FreeTextColor as appropriate.
• Preserve brackets, equals signs, setting names, and valid color syntax.
• Save the file as plain text to its original location.
• Close all SumatraPDF windows before retesting.
• Create one new annotation after restart.
• Verify that Windows is not launching another installed or portable copy.
• Move a portable copy to a user-writable folder if settings cannot persist.
• Back up and reversibly reset the settings file only if targeted edits fail.
• Run a clean portable test before reinstalling.

7. Frequently Asked Questions

7.1 Why does changing one highlight not change the next highlight?

You may have changed the properties of one existing annotation rather than the default in the Annotations section. Individual annotation properties affect that annotation. The HighlightColor default controls newly created highlights after the setting is saved and loaded.

7.2 Will changing HighlightColor recolor my existing highlights?

No. Existing annotations generally retain the color already stored with them. Change them individually if appropriate. Test the default by creating a new highlight after saving the setting and restarting SumatraPDF when necessary.

7.3 Why does the color work when launching SumatraPDF directly but not when double-clicking a PDF?

Windows is probably opening a different SumatraPDF executable through the PDF file association. This commonly occurs when both installed and portable copies exist. Open Advanced Options in each running copy to identify which settings file it uses, then correct the association or shortcut.

7.4 Can a read-only PDF cause the default color problem?

A read-only location or restricted document can prevent annotations from being saved, but it does not normally rewrite the configured default color. Test with a local PDF you are permitted to modify. Do not attempt to bypass document restrictions.

7.5 Do Ghostscript, codecs, or printer drivers control annotation colors?

Not for this specific symptom. Those components may matter for particular input formats, rendering paths, conversion workflows, or printing. Default PDF annotation colors are controlled by SumatraPDF's annotation settings. Investigate external components only when there is a separate format, display, or printing failure.

7.6 When should I stop troubleshooting?

Stop as soon as one newly created annotation of the tested type uses the intended color after reopening SumatraPDF. Existing annotations do not need to change for the default fix to be successful. Continuing to reset settings or reinstall software after that point can undo working preferences without providing a benefit.