diff --git a/src/acme2.js b/src/acme2.js
index 1a2f28c5b..538a058fa 100644
--- a/src/acme2.js
+++ b/src/acme2.js
@@ -88,10 +88,10 @@ Acme2.prototype.sendSignedRequest = async function (url, payload) {
 
     let [error, response] = await safe(superagent.get(this.directory.newNonce).timeout(30000).ok(() => true));
     if (error) throw new BoxError(BoxError.NETWORK_ERROR, `Network error sending signed request: ${error.message}`);
-    if (response.status !== 204) throw new BoxError(BoxError.EXTERNAL_ERROR, `Invalid response code when fetching nonce : ${response.status}`);
+    if (response.status !== 204) throw new BoxError(BoxError.ACME_ERROR, `Invalid response code when fetching nonce : ${response.status}`);
 
     const nonce = response.headers['Replay-Nonce'.toLowerCase()];
-    if (!nonce) throw new BoxError(BoxError.EXTERNAL_ERROR, 'No nonce in response');
+    if (!nonce) throw new BoxError(BoxError.ACME_ERROR, 'No nonce in response');
 
     debug('sendSignedRequest: using nonce %s for url %s', nonce, url);
 
@@ -129,7 +129,7 @@ Acme2.prototype.updateContact = async function (registrationUri) {
     };
 
     const result = await this.sendSignedRequest(registrationUri, JSON.stringify(payload));
-    if (result.status !== 200) throw new BoxError(BoxError.EXTERNAL_ERROR, `Failed to update contact. Expecting 200, got ${result.status} ${JSON.stringify(result.body)}`);
+    if (result.status !== 200) throw new BoxError(BoxError.ACME_ERROR, `Failed to update contact. Expecting 200, got ${result.status} ${JSON.stringify(result.body)}`);
 
     debug(`updateContact: contact of user updated to ${this.email}`);
 };
@@ -163,7 +163,7 @@ Acme2.prototype.ensureAccount = async function () {
     }
 
     // 200 if already exists. 201 for new accounts
-    if (result.status !== 200 && result.status !== 201) throw new BoxError(BoxError.EXTERNAL_ERROR, `Failed to register new account. Expecting 200 or 201, got ${result.status} ${JSON.stringify(result.body)}`);
+    if (result.status !== 200 && result.status !== 201) throw new BoxError(BoxError.ACME_ERROR, `Failed to register new account. Expecting 200 or 201, got ${result.status} ${JSON.stringify(result.body)}`);
 
     debug(`ensureAccount: user registered keyid: ${result.headers.location}`);
 
@@ -186,15 +186,15 @@ Acme2.prototype.newOrder = async function (domain) {
 
     const result = await this.sendSignedRequest(this.directory.newOrder, JSON.stringify(payload));
     if (result.status === 403) throw new BoxError(BoxError.ACCESS_DENIED, `Forbidden sending new order: ${result.body.detail}`);
-    if (result.status !== 201) throw new BoxError(BoxError.EXTERNAL_ERROR, `Failed to send new order. Expecting 201, got ${result.statusCode} ${JSON.stringify(result.body)}`);
+    if (result.status !== 201) throw new BoxError(BoxError.ACME_ERROR, `Failed to send new order. Expecting 201, got ${result.statusCode} ${JSON.stringify(result.body)}`);
 
     debug('newOrder: created order %s %j', domain, result.body);
 
     const order = result.body, orderUrl = result.headers.location;
 
-    if (!Array.isArray(order.authorizations)) throw new BoxError(BoxError.EXTERNAL_ERROR, 'invalid authorizations in order');
-    if (typeof order.finalize !== 'string') throw new BoxError(BoxError.EXTERNAL_ERROR, 'invalid finalize in order');
-    if (typeof orderUrl !== 'string') throw new BoxError(BoxError.EXTERNAL_ERROR, 'invalid order location in order header');
+    if (!Array.isArray(order.authorizations)) throw new BoxError(BoxError.ACME_ERROR, 'invalid authorizations in order');
+    if (typeof order.finalize !== 'string') throw new BoxError(BoxError.ACME_ERROR, 'invalid finalize in order');
+    if (typeof orderUrl !== 'string') throw new BoxError(BoxError.ACME_ERROR, 'invalid order location in order header');
 
     return { order, orderUrl };
 };
@@ -210,14 +210,14 @@ Acme2.prototype.waitForOrder = async function (orderUrl) {
         const result = await this.postAsGet(orderUrl);
         if (result.status !== 200) {
             debug(`waitForOrder: invalid response code getting uri ${result.status}`);
-            throw new BoxError(BoxError.EXTERNAL_ERROR, `Bad response code: ${result.status}`);
+            throw new BoxError(BoxError.ACME_ERROR, `Bad response when waiting for order. code: ${result.status}`);
         }
 
         debug('waitForOrder: status is "%s %j', result.body.status, result.body);
 
-        if (result.body.status === 'pending' || result.body.status === 'processing') throw new BoxError(BoxError.TRY_AGAIN, `Request is in ${result.body.status} state`);
+        if (result.body.status === 'pending' || result.body.status === 'processing') throw new BoxError(BoxError.ACME_ERROR, `Request is in ${result.body.status} state`);
         else if (result.body.status === 'valid' && result.body.certificate) return result.body.certificate;
-        else throw new BoxError(BoxError.EXTERNAL_ERROR, `Unexpected status or invalid response: ${JSON.stringify(result.body)}`);
+        else throw new BoxError(BoxError.ACME_ERROR, `Unexpected status or invalid response when waiting for order: ${JSON.stringify(result.body)}`);
     });
 };
 
@@ -249,7 +249,7 @@ Acme2.prototype.notifyChallengeReady = async function (challenge) {
     };
 
     const result = await this.sendSignedRequest(challenge.url, JSON.stringify(payload));
-    if (result.status !== 200) throw new BoxError(BoxError.EXTERNAL_ERROR, `Failed to notify challenge. Expecting 200, got ${result.statusCode} ${JSON.stringify(result.body)}`);
+    if (result.status !== 200) throw new BoxError(BoxError.ACME_ERROR, `Failed to notify challenge. Expecting 200, got ${result.statusCode} ${JSON.stringify(result.body)}`);
 };
 
 Acme2.prototype.waitForChallenge = async function (challenge) {
@@ -263,14 +263,14 @@ Acme2.prototype.waitForChallenge = async function (challenge) {
         const result = await this.postAsGet(challenge.url);
         if (result.status !== 200) {
             debug(`waitForChallenge: invalid response code getting uri ${result.status}`);
-            throw new BoxError(BoxError.EXTERNAL_ERROR, 'Bad response code:' + result.statusCode);
+            throw new BoxError(BoxError.ACME_ERROR, `Bad response code when waiting for challenge : ${result.status}`);
         }
 
         debug(`waitForChallenge: status is "${result.body.status}" "${JSON.stringify(result.body)}"`);
 
-        if (result.body.status === 'pending') throw new BoxError(BoxError.TRY_AGAIN);
+        if (result.body.status === 'pending') throw new BoxError(BoxError.ACME_ERROR, 'Challenge is in pending state');
         else if (result.body.status === 'valid') return;
-        else throw new BoxError(BoxError.EXTERNAL_ERROR, `Unexpected status: ${result.body.status}`);
+        else throw new BoxError(BoxError.ACME_ERROR, `Unexpected status when waiting for challenge: ${result.body.status}`);
     });
 };
 
@@ -288,7 +288,7 @@ Acme2.prototype.signCertificate = async function (domain, finalizationUrl, csrDe
 
     const result = await this.sendSignedRequest(finalizationUrl, JSON.stringify(payload));
     // 429 means we reached the cert limit for this domain
-    if (result.status !== 200) throw new BoxError(BoxError.EXTERNAL_ERROR, `Failed to sign certificate. Expecting 200, got ${result.status} ${JSON.stringify(result.body)}`);
+    if (result.status !== 200) throw new BoxError(BoxError.ACME_ERROR, `Failed to sign certificate. Expecting 200, got ${result.status} ${JSON.stringify(result.body)}`);
 };
 
 Acme2.prototype.createKeyAndCsr = async function (hostname, keyFilePath, csrFilePath) {
@@ -339,8 +339,8 @@ Acme2.prototype.downloadCertificate = async function (hostname, certUrl, certFil
         debug('downloadCertificate: downloading certificate');
 
         const result = await this.postAsGet(certUrl);
-        if (result.statusCode === 202) throw new BoxError(BoxError.TRY_AGAIN, 'Retry downloading certificate');
-        if (result.statusCode !== 200) throw new BoxError(BoxError.EXTERNAL_ERROR, `Failed to get cert. Expecting 200, got ${result.statusCode} ${JSON.stringify(result.body)}`);
+        if (result.statusCode === 202) throw new BoxError(BoxError.ACME_ERROR, 'Retry downloading certificate');
+        if (result.statusCode !== 200) throw new BoxError(BoxError.ACME_ERROR, `Failed to get cert. Expecting 200, got ${result.statusCode} ${JSON.stringify(result.body)}`);
 
         const fullChainPem = result.body; // buffer
 
@@ -358,7 +358,7 @@ Acme2.prototype.prepareHttpChallenge = async function (hostname, domain, authori
 
     debug('prepareHttpChallenge: challenges: %j', authorization);
     let httpChallenges = authorization.challenges.filter(function(x) { return x.type === 'http-01'; });
-    if (httpChallenges.length === 0) throw new BoxError(BoxError.EXTERNAL_ERROR, 'no http challenges');
+    if (httpChallenges.length === 0) throw new BoxError(BoxError.ACME_ERROR, 'no http challenges');
     let challenge = httpChallenges[0];
 
     debug('prepareHttpChallenge: preparing for challenge %j', challenge);
@@ -407,7 +407,7 @@ Acme2.prototype.prepareDnsChallenge = async function (hostname, domain, authoriz
 
     debug('prepareDnsChallenge: challenges: %j', authorization);
     const dnsChallenges = authorization.challenges.filter(function(x) { return x.type === 'dns-01'; });
-    if (dnsChallenges.length === 0) throw new BoxError(BoxError.EXTERNAL_ERROR, 'no dns challenges');
+    if (dnsChallenges.length === 0) throw new BoxError(BoxError.ACME_ERROR, 'no dns challenges');
     const challenge = dnsChallenges[0];
 
     const keyAuthorization = this.getKeyAuthorization(challenge.token);
@@ -452,7 +452,7 @@ Acme2.prototype.prepareChallenge = async function (hostname, domain, authorizati
     debug(`prepareChallenge: http: ${this.performHttpAuthorization}`);
 
     const response = await this.postAsGet(authorizationUrl);
-    if (response.status !== 200) throw new BoxError(BoxError.EXTERNAL_ERROR, `Invalid response code getting authorization : ${response.status}`);
+    if (response.status !== 200) throw new BoxError(BoxError.ACME_ERROR, `Invalid response code getting authorization : ${response.status}`);
 
     const authorization = response.body;
 
@@ -512,11 +512,11 @@ Acme2.prototype.loadDirectory = async function () {
     await promiseRetry({ times: 3, interval: 20000 }, async () => {
         const response = await superagent.get(this.caDirectory).timeout(30000).ok(() => true);
 
-        if (response.status !== 200) throw new BoxError(BoxError.EXTERNAL_ERROR, `Invalid response code when fetching directory : ${response.status}`);
+        if (response.status !== 200) throw new BoxError(BoxError.ACME_ERROR, `Invalid response code when fetching directory : ${response.status}`);
 
         if (typeof response.body.newNonce !== 'string' ||
             typeof response.body.newOrder !== 'string' ||
-            typeof response.body.newAccount !== 'string') throw new BoxError(BoxError.EXTERNAL_ERROR, `Invalid response body : ${response.body}`);
+            typeof response.body.newAccount !== 'string') throw new BoxError(BoxError.ACME_ERROR, `Invalid response body : ${response.body}`);
 
         this.directory = response.body;
     });
diff --git a/src/boxerror.js b/src/boxerror.js
index e6bebb58e..a7721fdeb 100644
--- a/src/boxerror.js
+++ b/src/boxerror.js
@@ -33,6 +33,7 @@ function BoxError(reason, errorOrMessage, override) {
 }
 util.inherits(BoxError, Error);
 BoxError.ACCESS_DENIED = 'Access Denied';
+BoxError.ACME_ERROR = 'Acme Error';
 BoxError.ADDONS_ERROR = 'Addons Error';
 BoxError.ALREADY_EXISTS = 'Already Exists';
 BoxError.BAD_FIELD = 'Bad Field';
@@ -91,6 +92,7 @@ BoxError.toHttpError = function (error) {
     case BoxError.INVALID_CREDENTIALS:
         return new HttpError(412, error);
     case BoxError.EXTERNAL_ERROR:
+    case BoxError.ACME_ERROR:
     case BoxError.NETWORK_ERROR:
     case BoxError.FS_ERROR:
     case BoxError.MOUNT_ERROR: