diff --git a/app/server/lib/DocApi.ts b/app/server/lib/DocApi.ts
index 1e0589e547..1216345841 100644
--- a/app/server/lib/DocApi.ts
+++ b/app/server/lib/DocApi.ts
@@ -1574,10 +1574,6 @@ export class DocWorkerApi {
         await this._getDownloadOptions(req) :
         {
           filename: await this._getDownloadFilename(req),
-          tableId: "",
-          viewSectionId: undefined,
-          filters: [],
-          sortOrder: [],
           header: "label",
         };
       await downloadXLSX(activeDoc, req, res, options);
diff --git a/app/server/lib/Export.ts b/app/server/lib/Export.ts
index b99781a3aa..209adc61ba 100644
--- a/app/server/lib/Export.ts
+++ b/app/server/lib/Export.ts
@@ -17,7 +17,7 @@ import { BaseFormatter, createFullFormatterFromDocData } from "app/common/ValueF
 import { ActiveDoc } from "app/server/lib/ActiveDoc";
 import { RequestWithLogin } from "app/server/lib/Authorizer";
 import { docSessionFromRequest } from "app/server/lib/DocSession";
-import { optIntegerParam, optJsonParam, optStringParam, stringParam } from "app/server/lib/requestUtils";
+import { optIntegerParam, optJsonParam, optStringParam } from "app/server/lib/requestUtils";
 import { ServerColumnGetters } from "app/server/lib/ServerColumnGetters";
 
 import * as express from "express";
@@ -97,7 +97,7 @@ export type ExportHeader = "colId" | "label";
  * Export parameters that identifies a section, filters, sort order.
  */
 export interface ExportParameters {
-  tableId: string;          // Value of '' is an instruction to export all tables.
+  tableId?: string;
   viewSectionId?: number;
   sortOrder?: number[];
   filters?: Filter[];
@@ -116,7 +116,7 @@ export interface DownloadOptions extends ExportParameters {
  * Gets export parameters from a request.
  */
 export function parseExportParameters(req: express.Request): ExportParameters {
-  const tableId = stringParam(req.query.tableId, "tableId");
+  const tableId = optStringParam(req.query.tableId, "tableId");
   const viewSectionId = optIntegerParam(req.query.viewSection, "viewSection");
   const sortOrder = optJsonParam(req.query.activeSortSpec, []) as number[];
   const filters: Filter[] = optJsonParam(req.query.filters, []);
diff --git a/app/server/lib/ExportDSV.ts b/app/server/lib/ExportDSV.ts
index 7bf35e8e58..93379e77db 100644
--- a/app/server/lib/ExportDSV.ts
+++ b/app/server/lib/ExportDSV.ts
@@ -31,12 +31,19 @@ export async function downloadDSV(
   const { filename, tableId, viewSectionId, filters, sortOrder, linkingFilter, delimiter, header } = options;
   const extension = getDSVFileExtension(delimiter);
   log.info(`Generating ${extension} file...`);
-  const data = viewSectionId ?
-    await makeDSVFromViewSection({
+  let data;
+  if (viewSectionId) {
+    data = await makeDSVFromViewSection({
       activeDoc, viewSectionId, sortOrder: sortOrder || null, filters: filters || null,
       linkingFilter: linkingFilter || null, header, delimiter, req,
-    }) :
-    await makeDSVFromTable({ activeDoc, tableId, header, delimiter, req });
+    });
+  }
+  else {
+    if (!tableId) {
+      throw new ApiError("tableId parameter is required", 400);
+    }
+    data = await makeDSVFromTable({ activeDoc, tableId, header, delimiter, req });
+  }
   res.set("Content-Type", getDSVMimeType(delimiter));
   res.setHeader("Content-Disposition", contentDisposition(filename + extension));
   res.send(data);
diff --git a/app/server/lib/ExportTableSchema.ts b/app/server/lib/ExportTableSchema.ts
index 265c3c71d9..8a9c1374a0 100644
--- a/app/server/lib/ExportTableSchema.ts
+++ b/app/server/lib/ExportTableSchema.ts
@@ -43,6 +43,9 @@ export async function collectTableSchemaInFrictionlessFormat(
   if (!activeDoc.docData) {
     throw new Error("No docData in active document");
   }
+  if (!tableId) {
+    throw new ApiError("tableId parameter is required", 400);
+  }
 
   // Look up the table to make a CSV from.
   const settings = activeDoc.docData.docSettings();
diff --git a/test/server/lib/DocApi.ts b/test/server/lib/DocApi.ts
index 72ee0f400d..1381fa4503 100644
--- a/test/server/lib/DocApi.ts
+++ b/test/server/lib/DocApi.ts
@@ -3287,6 +3287,13 @@ function testDocApi(settings: {
     assert.notEqual(resp.data, null);
   });
 
+  it("GET /docs/{did}/download/xlsx returns 200 if tableId is missing and header present", async function() {
+    const resp = await axios.get(
+      `${serverUrl}/api/docs/${docIds.TestDoc}/download/xlsx?header=label`, chimpy);
+    assert.equal(resp.status, 200);
+    assert.notEqual(resp.data, null);
+  });
+
   it("POST /workspaces/{wid}/import handles empty filenames", async function() {
     if (!process.env.TEST_REDIS_URL) {
       this.skip();