diff --git a/client/app_control.cpp b/client/app_control.cpp
index 750e53de66..4a83dbc317 100644
--- a/client/app_control.cpp
+++ b/client/app_control.cpp
@@ -69,6 +69,7 @@ using std::vector;
 #include "shmem.h"
 #include "str_replace.h"
 #include "str_util.h"
+#include "url.h"
 #include "util.h"
 
 #include "client_msgs.h"
@@ -1633,7 +1634,7 @@ void ACTIVE_TASK::read_task_state_file() {
         );
         return;
     }
-    if (strcmp(s, result->project->master_url)) {
+    if (!urls_match(s, result->project->master_url)) {
         msg_printf(wup->project, MSG_INTERNAL_ERROR,
             "wrong project URL in task state file"
         );
diff --git a/client/client_state.cpp b/client/client_state.cpp
index b8aed81b8d..ffd6f29bdd 100644
--- a/client/client_state.cpp
+++ b/client/client_state.cpp
@@ -51,6 +51,7 @@
 #include "parse.h"
 #include "str_replace.h"
 #include "str_util.h"
+#include "url.h"
 #include "util.h"
 #ifdef _WIN32
 #include "run_app_windows.h"
@@ -1189,21 +1190,21 @@ bool CLIENT_STATE::poll_slow_events() {
 
 #endif // ifndef SIM
 
-// See if the project specified by master_url already exists
-// in the client state record.  Ignore any trailing "/" characters
+// Find the project with the given master_url.
+// Ignore differences in protocol, case, and trailing /
 //
 PROJECT* CLIENT_STATE::lookup_project(const char* master_url) {
-    int len1, len2;
-    char *mu;
+    char buf[256];
 
-    len1 = (int)strlen(master_url);
-    if (master_url[strlen(master_url)-1] == '/') len1--;
+    safe_strcpy(buf, master_url);
+    canonicalize_master_url(buf, sizeof(buf));
+    char* p = strstr(buf, "//");
+    if (!p) return NULL;
 
     for (unsigned int i=0; i<projects.size(); i++) {
-        mu = projects[i]->master_url;
-        len2 = (int)strlen(mu);
-        if (mu[strlen(mu)-1] == '/') len2--;
-        if (!strncmp(master_url, projects[i]->master_url, max(len1,len2))) {
+        char* q = strstr(projects[i]->master_url, "//");
+        if (!q) continue;
+        if (!strcmp(p, q)) {
             return projects[i];
         }
     }
diff --git a/client/gui_rpc_server_ops.cpp b/client/gui_rpc_server_ops.cpp
index b684c356e7..c409aa5ae1 100644
--- a/client/gui_rpc_server_ops.cpp
+++ b/client/gui_rpc_server_ops.cpp
@@ -748,7 +748,7 @@ static void handle_get_project_init_status(GUI_RPC_CONN& grc) {
     //
     for (unsigned i=0; i<gstate.projects.size(); i++) { 
         PROJECT* p = gstate.projects[i]; 
-        if (!strcmp(p->master_url, gstate.project_init.url)) { 
+        if (urls_match(p->master_url, gstate.project_init.url)) { 
             gstate.project_init.remove(); 
             break; 
         } 
diff --git a/client/log_flags.cpp b/client/log_flags.cpp
index 40d4bad109..81a1a86443 100644
--- a/client/log_flags.cpp
+++ b/client/log_flags.cpp
@@ -37,6 +37,7 @@
 #include "parse.h"
 #include "str_replace.h"
 #include "str_util.h"
+#include "url.h"
 
 #include "client_state.h"
 #include "client_msgs.h"
@@ -681,7 +682,7 @@ void process_gpu_exclusions() {
             for (j=0; j<cc_config.exclude_gpus.size(); j++) {
                 EXCLUDE_GPU& eg = cc_config.exclude_gpus[j];
                 if (!eg.type.empty() && (eg.type != cp.type)) continue;
-                if (strcmp(eg.url.c_str(), p->master_url)) continue;
+                if (!urls_match(eg.url.c_str(), p->master_url)) continue;
                 COPROC_INSTANCE_BITMAP mask;
                 if (eg.device_num >= 0) {
                     int index = cp.device_num_index(eg.device_num);
@@ -775,7 +776,7 @@ bool gpu_excluded(APP* app, COPROC& cp, int ind) {
     PROJECT* p = app->project;
     for (unsigned int i=0; i<cc_config.exclude_gpus.size(); i++) {
         EXCLUDE_GPU& eg = cc_config.exclude_gpus[i];
-        if (strcmp(eg.url.c_str(), p->master_url)) continue;
+        if (!urls_match(eg.url.c_str(), p->master_url)) continue;
         if (!eg.type.empty() && (eg.type != cp.type)) continue;
         if (!eg.appname.empty() && (eg.appname != app->name)) continue;
         if (eg.device_num >= 0 && eg.device_num != cp.device_nums[ind]) continue;
diff --git a/lib/url.cpp b/lib/url.cpp
index 1a7e77aff2..5d9ed3a268 100644
--- a/lib/url.cpp
+++ b/lib/url.cpp
@@ -248,6 +248,15 @@ bool is_https_transition(const char* url1, const char* url2) {
     return true;
 }
 
+// return true if url1 and url2 are the same except protocol
+//
+bool urls_match(const char* url1, const char* url2) {
+    const char* p = strstr(url1, "//");
+    const char* q = strstr(url2, "//");
+    if (!p || !q) return false;
+    return strcmp(p, q) == 0;
+}
+
 // is the string a valid master URL, in canonical form?
 //
 bool valid_master_url(char* buf) {
diff --git a/lib/url.h b/lib/url.h
index fd27e41e75..943c9a21dc 100644
--- a/lib/url.h
+++ b/lib/url.h
@@ -47,5 +47,5 @@ extern void canonicalize_master_url(char *url, int len);
 extern void canonicalize_master_url(std::string&);
 extern bool is_https(const char*);
 extern bool is_https_transition(const char* ur1l, const char* url2);
-
+extern bool urls_match(const char* url1, const char* url2);
 #endif