diff --git a/common/changes/@itwin/core-backend/imodel-not-open-404_2022-03-10-14-47.json b/common/changes/@itwin/core-backend/imodel-not-open-404_2022-03-10-14-47.json
new file mode 100644
index 000000000000..99b35bb89b62
--- /dev/null
+++ b/common/changes/@itwin/core-backend/imodel-not-open-404_2022-03-10-14-47.json
@@ -0,0 +1,10 @@
+{
+  "changes": [
+    {
+      "packageName": "@itwin/core-backend",
+      "comment": "",
+      "type": "none"
+    }
+  ],
+  "packageName": "@itwin/core-backend"
+}
\ No newline at end of file
diff --git a/common/changes/@itwin/core-common/imodel-not-open-404_2022-03-10-14-47.json b/common/changes/@itwin/core-common/imodel-not-open-404_2022-03-10-14-47.json
new file mode 100644
index 000000000000..d1ac065f5d72
--- /dev/null
+++ b/common/changes/@itwin/core-common/imodel-not-open-404_2022-03-10-14-47.json
@@ -0,0 +1,10 @@
+{
+  "changes": [
+    {
+      "packageName": "@itwin/core-common",
+      "comment": "",
+      "type": "none"
+    }
+  ],
+  "packageName": "@itwin/core-common"
+}
\ No newline at end of file
diff --git a/core/backend/src/rpc-impl/RpcBriefcaseUtility.ts b/core/backend/src/rpc-impl/RpcBriefcaseUtility.ts
index 2480fe43f7aa..364ae6951bfb 100644
--- a/core/backend/src/rpc-impl/RpcBriefcaseUtility.ts
+++ b/core/backend/src/rpc-impl/RpcBriefcaseUtility.ts
@@ -113,9 +113,7 @@ export class RpcBriefcaseUtility {
    * @param the IModelRpcProps to locate the opened iModel.
    */
   public static async findOpenIModel(accessToken: AccessToken, iModel: IModelRpcProps) {
-    const iModelDb = IModelDb.tryFindByKey(iModel.key);
-    if (undefined === iModelDb)
-      throw new IModelError(IModelStatus.NotOpen, "iModel is not opened", () => iModel);
+    const iModelDb = IModelDb.findByKey(iModel.key);
 
     // call reattach, just in case this is a V2 checkpoint whose accessToken is about to expire.
     await iModelDb.reattachDaemon(accessToken);
diff --git a/core/common/src/rpc/core/RpcInvocation.ts b/core/common/src/rpc/core/RpcInvocation.ts
index cd073c87690d..312b5fd2d9b7 100644
--- a/core/common/src/rpc/core/RpcInvocation.ts
+++ b/core/common/src/rpc/core/RpcInvocation.ts
@@ -216,15 +216,12 @@ export class RpcInvocation {
 
     const result = await RpcMarshaling.serialize(this.protocol, reason);
 
-    let isNoContentError = false;
-    try { isNoContentError = reason.errorNumber === IModelStatus.NoContent; } catch { }
-
     if (reason instanceof RpcPendingResponse) {
       this._pending = true;
       this._threw = false;
       result.objects = reason.message;
       this.protocol.events.raiseEvent(RpcProtocolEvent.BackendReportedPending, this);
-    } else if (this.supportsNoContent() && isNoContentError) {
+    } else if (this.supportsNoContent() && reason?.errorNumber === IModelStatus.NoContent) {
       this._noContent = true;
       this._threw = false;
       this.protocol.events.raiseEvent(RpcProtocolEvent.BackendReportedNoContent, this);