e9c3757c29ec6d08b6232e0a671fe5970bb58e2e
lrnassar
  Wed Feb 18 19:21:54 2026 -0800
Feedback from CR, refs #37124

diff --git src/hg/lib/trackHub.c src/hg/lib/trackHub.c
index 846159a0f7f..4be26e187de 100644
--- src/hg/lib/trackHub.c
+++ src/hg/lib/trackHub.c
@@ -1435,43 +1435,44 @@
     /* RMH: Added support for bigRmsk track hub data type */
     else if (startsWithWord("bigNarrowPeak", type) || startsWithWord("bigBed", type) ||
                 startsWithWord("bigGenePred", type)  || startsWithWord("bigPsl", type)||
                 startsWithWord("bigChain", type)|| startsWithWord("bigMaf", type) ||
                 startsWithWord("bigBarChart", type) || startsWithWord("bigInteract", type) ||
                 startsWithWord("bigLolly", type) || startsWithWord("bigRmsk",type))
         {
         /* Just open and close to verify file exists and is correct type. */
         struct bbiFile *bbi = bigBedFileOpen(bigDataUrl);
         char *typeString = cloneString(type);
         nextWord(&typeString);
         if (startsWithWord("bigBed", type) && (typeString != NULL))
             {
             unsigned numFields = sqlUnsigned(nextWord(&typeString));
             if (numFields > bbi->fieldCount)
-                errAbort("bigBed file '%s' has %d fields, but track \"%s\" declares 'type bigBed %d'. Either regenerate the bigBed with the correct number of fields, or change the type line to 'type bigBed %d' to match the file.", bigDataUrl, bbi->fieldCount, trackHubSkipHubName(tdb->track), numFields, bbi->fieldCount);
+                errAbort("bigBed file '%s' has %d fields, but track \"%s\" declares 'type bigBed %d'. Either regenerate the bigBed with the correct number of fields, or change the type line to match the file's field count.", bigDataUrl, bbi->fieldCount, trackHubSkipHubName(tdb->track), numFields);
             }
         bbiFileClose(&bbi);
         }
     else if (startsWithWord("vcfTabix", type) || startsWithWord("vcfPhasedTrio", type))
         {
         /* Just open and close to verify file exists and is correct type. */
         struct vcfFile *vcf = vcfTabixFileAndIndexMayOpen(bigDataUrl, bigDataIndex, NULL, 0, 0, 1, 1);
         if (vcf == NULL)
             // Warnings already indicated whether the tabix file is missing etc.
             errAbort("Couldn't open %s and/or its tabix index (.tbi) file for track %s. "
                      "Both the .vcf.gz file and a matching .vcf.gz.tbi index must be publicly accessible "
-                     "at the same URL path. Generate the index with: tabix -p vcf yourFile.vcf.gz",
+                     "at the same URL path. Generate the index with: tabix -p vcf yourFile.vcf.gz "
+                     "See https://genome.ucsc.edu/goldenPath/help/vcf.html",
                      bigDataUrl, trackHubSkipHubName(tdb->track));
         vcfFileFree(&vcf);
         }
     else if (startsWithWord("bam", type))
         {
         bamFileAndIndexMustExist(bigDataUrl, bigDataIndex);
         }
     else if (startsWithWord("longTabix", type))
         {
         struct bedTabixFile *btf = bedTabixFileMayOpen(bigDataUrl, NULL, 0, 0);
         if (btf == NULL)
             errAbort("Couldn't open %s and/or its tabix index (.tbi) file for track %s. "
                      "Both the file and a matching .tbi index must be publicly accessible "
                      "at the same URL path.", bigDataUrl, trackHubSkipHubName(tdb->track));
         bedTabixFileClose(&btf);