diff --git a/packages/electron-builder-lib/src/publish/PublishManager.ts b/packages/electron-builder-lib/src/publish/PublishManager.ts
index b7d555993cd..646fd947b30 100644
--- a/packages/electron-builder-lib/src/publish/PublishManager.ts
+++ b/packages/electron-builder-lib/src/publish/PublishManager.ts
@@ -84,7 +84,7 @@ export class PublishManager implements PublishContext {
         return
       }
 
-      const publishConfig = await getAppUpdatePublishConfiguration(packager, event.arch)
+      const publishConfig = await getAppUpdatePublishConfiguration(packager, event.arch, this.isPublish)
       if (publishConfig != null) {
         await writeFile(path.join(packager.getResourcesDir(event.appOutDir), "app-update.yml"), serializeToYaml(publishConfig))
       }
@@ -125,7 +125,7 @@ export class PublishManager implements PublishContext {
   private async artifactCreated(event: ArtifactCreated) {
     const packager = event.packager
     const target = event.target
-    const publishConfigs = event.publishConfig == null ? await getPublishConfigs(packager, target == null ? null : target.options, event.arch) : [event.publishConfig]
+    const publishConfigs = event.publishConfig == null ? await getPublishConfigs(packager, target == null ? null : target.options, event.arch, this.isPublish) : [event.publishConfig]
 
     if (debug.enabled) {
       debug(`artifactCreated (isPublish: ${this.isPublish}): ${safeStringifyJson(event, new Set(["packager"]))},\n  publishConfigs: ${safeStringifyJson(publishConfigs)}`)
@@ -188,8 +188,8 @@ export class PublishManager implements PublishContext {
   }
 }
 
-export async function getAppUpdatePublishConfiguration(packager: PlatformPackager<any>, arch: Arch) {
-  const publishConfigs = await getPublishConfigsForUpdateInfo(packager, await getPublishConfigs(packager, null, arch), arch)
+export async function getAppUpdatePublishConfiguration(packager: PlatformPackager<any>, arch: Arch, errorIfCannot: boolean) {
+  const publishConfigs = await getPublishConfigsForUpdateInfo(packager, await getPublishConfigs(packager, null, arch, errorIfCannot), arch)
   if (publishConfigs == null || publishConfigs.length === 0) {
     return null
   }
@@ -297,7 +297,7 @@ export function computeDownloadUrl(publishConfiguration: PublishConfiguration, f
   return `${baseUrl}/${encodeURI(fileName)}`
 }
 
-export async function getPublishConfigs(packager: PlatformPackager<any>, targetSpecificOptions: PlatformSpecificBuildOptions | null | undefined, arch: Arch | null): Promise<Array<PublishConfiguration> | null> {
+export async function getPublishConfigs(packager: PlatformPackager<any>, targetSpecificOptions: PlatformSpecificBuildOptions | null | undefined, arch: Arch | null, errorIfCannot: boolean): Promise<Array<PublishConfiguration> | null> {
   let publishers
 
   // check build.nsis (target)
@@ -335,7 +335,7 @@ export async function getPublishConfigs(packager: PlatformPackager<any>, targetS
 
     if (serviceName != null) {
       log.debug(null, `Detect ${serviceName} as publish provider`)
-      return [(await getResolvedPublishConfig(packager, {provider: serviceName}, arch))!]
+      return [(await getResolvedPublishConfig(packager, {provider: serviceName}, arch, errorIfCannot))!]
     }
   }
 
@@ -344,7 +344,7 @@ export async function getPublishConfigs(packager: PlatformPackager<any>, targetS
   }
 
   debug(`Explicit publish provider: ${safeStringifyJson(publishers)}`)
-  return await (BluebirdPromise.map(asArray(publishers), it => getResolvedPublishConfig(packager, typeof it === "string" ? {provider: it} : it, arch)) as Promise<Array<PublishConfiguration>>)
+  return await (BluebirdPromise.map(asArray(publishers), it => getResolvedPublishConfig(packager, typeof it === "string" ? {provider: it} : it, arch, errorIfCannot)) as Promise<Array<PublishConfiguration>>)
 }
 
 function isSuitableWindowsTarget(target: Target) {
@@ -371,7 +371,7 @@ function isDetectUpdateChannel(packager: PlatformPackager<any>) {
   return value == null ? packager.config.detectUpdateChannel !== false : value
 }
 
-async function getResolvedPublishConfig(packager: PlatformPackager<any>, options: PublishConfiguration, arch: Arch | null, errorIfCannot: boolean = true): Promise<PublishConfiguration | GithubOptions | BintrayOptions | null> {
+async function getResolvedPublishConfig(packager: PlatformPackager<any>, options: PublishConfiguration, arch: Arch | null, errorIfCannot: boolean): Promise<PublishConfiguration | GithubOptions | BintrayOptions | null> {
   options = {...options}
   expandPublishConfig(options, packager, arch)
 
@@ -395,7 +395,7 @@ async function getResolvedPublishConfig(packager: PlatformPackager<any>, options
 
   const providerClass = requireProviderClass(options.provider)
   if (providerClass != null && providerClass.checkAndResolveOptions != null) {
-    await providerClass.checkAndResolveOptions(options, channelFromAppVersion)
+    await providerClass.checkAndResolveOptions(options, channelFromAppVersion, errorIfCannot)
     return options
   }
 
diff --git a/packages/electron-builder-lib/src/targets/AppImageTarget.ts b/packages/electron-builder-lib/src/targets/AppImageTarget.ts
index 228dcc2b82c..54158c6a6b2 100644
--- a/packages/electron-builder-lib/src/targets/AppImageTarget.ts
+++ b/packages/electron-builder-lib/src/targets/AppImageTarget.ts
@@ -70,7 +70,7 @@ export default class AppImageTarget extends Target {
       return
     }
 
-    const publishConfig = await getAppUpdatePublishConfiguration(packager, arch)
+    const publishConfig = await getAppUpdatePublishConfiguration(packager, arch, false /* in any case validation will be done on publish */)
     if (publishConfig != null) {
       await outputFile(path.join(packager.getResourcesDir(stageDir.getTempFile("app")), "app-update.yml"), serializeToYaml(publishConfig))
     }
diff --git a/packages/electron-builder-lib/src/targets/nsis/WebInstallerTarget.ts b/packages/electron-builder-lib/src/targets/nsis/WebInstallerTarget.ts
index 90b6bbee737..bdf5d199816 100644
--- a/packages/electron-builder-lib/src/targets/nsis/WebInstallerTarget.ts
+++ b/packages/electron-builder-lib/src/targets/nsis/WebInstallerTarget.ts
@@ -23,7 +23,7 @@ export class WebInstallerTarget extends NsisTarget {
 
     let appPackageUrl = options.appPackageUrl
     if (appPackageUrl == null) {
-      const publishConfigs = await getPublishConfigsForUpdateInfo(packager, await getPublishConfigs(packager, this.options, null), null)
+      const publishConfigs = await getPublishConfigsForUpdateInfo(packager, await getPublishConfigs(packager, this.options, null, false), null)
       if (publishConfigs == null || publishConfigs.length === 0) {
         throw new Error("Cannot compute app package download URL")
       }
diff --git a/packages/electron-publisher-s3/src/s3Publisher.ts b/packages/electron-publisher-s3/src/s3Publisher.ts
index 1296bb6adfd..7d557776fac 100644
--- a/packages/electron-publisher-s3/src/s3Publisher.ts
+++ b/packages/electron-publisher-s3/src/s3Publisher.ts
@@ -1,5 +1,5 @@
 import S3, { ClientConfiguration, ServerSideEncryption, StorageClass } from "aws-sdk/clients/s3"
-import { InvalidConfigurationError } from "builder-util"
+import { InvalidConfigurationError, log } from "builder-util"
 import { S3Options } from "builder-util-runtime"
 import { PublishContext } from "electron-publish"
 import { BaseS3Publisher } from "./BaseS3Publisher"
@@ -11,7 +11,7 @@ export default class S3Publisher extends BaseS3Publisher {
     super(context, info)
   }
 
-  static async checkAndResolveOptions(options: S3Options, channelFromAppVersion: string | null) {
+  static async checkAndResolveOptions(options: S3Options, channelFromAppVersion: string | null, errorIfCannot: boolean) {
     const bucket = options.bucket
     if (bucket == null) {
       throw new InvalidConfigurationError(`Please specify "bucket" for "s3" publish provider`)
@@ -20,7 +20,17 @@ export default class S3Publisher extends BaseS3Publisher {
     if (options.endpoint == null && (bucket.includes(".") && options.region == null)) {
       // on dotted bucket names, we need to use a path-based endpoint URL. Path-based endpoint URLs need to include the region.
       const s3 = new S3({signatureVersion: "v4"})
-      options.region = (await s3.getBucketLocation({Bucket: bucket}).promise()).LocationConstraint
+      try {
+        options.region = (await s3.getBucketLocation({Bucket: bucket}).promise()).LocationConstraint
+      }
+      catch (e) {
+        if (errorIfCannot) {
+          throw e
+        }
+        else {
+          log.warn(`cannot compute region for bucket (required because on dotted bucket names, we need to use a path-based endpoint URL): ${e}`)
+        }
+      }
     }
 
     if (options.channel == null && channelFromAppVersion != null) {
diff --git a/packages/electron-publisher-s3/src/spacesPublisher.ts b/packages/electron-publisher-s3/src/spacesPublisher.ts
index 1e34778f2d1..0dc8502020c 100644
--- a/packages/electron-publisher-s3/src/spacesPublisher.ts
+++ b/packages/electron-publisher-s3/src/spacesPublisher.ts
@@ -11,7 +11,7 @@ export default class SpacesPublisher extends BaseS3Publisher {
     super(context, info)
   }
 
-  static async checkAndResolveOptions(options: SpacesOptions, channelFromAppVersion: string | null) {
+  static async checkAndResolveOptions(options: SpacesOptions, channelFromAppVersion: string | null, errorIfCannot: boolean) {
     if (options.name == null) {
       throw new InvalidConfigurationError(`Please specify "name" for "spaces" publish provider (see https://www.electron.build/configuration/publish#spacesoptions)`)
     }
diff --git a/test/out/windows/__snapshots__/oneClickInstallerTest.js.snap b/test/out/windows/__snapshots__/oneClickInstallerTest.js.snap
index df86995921a..93f648e2919 100644
--- a/test/out/windows/__snapshots__/oneClickInstallerTest.js.snap
+++ b/test/out/windows/__snapshots__/oneClickInstallerTest.js.snap
@@ -1,5 +1,17 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
+exports[`big file pack 1`] = `
+Object {
+  "win": Array [
+    Object {
+      "arch": "x64",
+      "file": "Test App ßW Setup 1.1.0.exe",
+      "safeArtifactName": "TestApp-Setup-1.1.0.exe",
+    },
+  ],
+}
+`;
+
 exports[`custom include 1`] = `
 Object {
   "win": Array [
diff --git a/test/src/PublishManagerTest.ts b/test/src/PublishManagerTest.ts
index 1be2631e7e4..90a59fe7e4f 100644
--- a/test/src/PublishManagerTest.ts
+++ b/test/src/PublishManagerTest.ts
@@ -51,4 +51,17 @@ test.ifAll.ifNotWindows("os macro", app({
     await assertThat(dir).isDirectory()
     await checkDirContents(dir)
   }
+}))
+
+// https://github.com/electron-userland/electron-builder/issues/2670
+test.ifAll.ifNotWindows("dotted s3 bucket", app({
+  targets: createTargets([Platform.LINUX], "zip"),
+  config: {
+    publish: {
+      provider: "s3",
+      bucket: "bucket.dotted.name",
+    },
+  },
+}, {
+  publish: "never"
 }))
\ No newline at end of file