diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3dbf5ed6..daa6452b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -19,9 +19,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Switched from Travis-CI to Github Actions
 
+### Fixed
+
+- Avoid warning if path of uploaded file is longer than the maximum allowed path length
+
 ### Deprecated
 
 - `Redmine\Api\AbstractApi::lastCallFailed()` is deprecated, use `Redmine\Client\Client::getLastResponseStatusCode()` instead
+- Uploading an attachment using `Redmine\Api\Attachment::upload()` with filepath is deprectead, use `file_get_contents()` to upload the file content instead
 
 ## [v2.0.1](https://github.com/kbsali/php-redmine-api/compare/v2.0.0...v2.0.1) - 2021-09-22
 
diff --git a/src/Redmine/Client/ClientApiTrait.php b/src/Redmine/Client/ClientApiTrait.php
index b8b47bb4..a426f7b5 100644
--- a/src/Redmine/Client/ClientApiTrait.php
+++ b/src/Redmine/Client/ClientApiTrait.php
@@ -53,4 +53,20 @@ public function getApi(string $name): Api
 
         return $this->apiInstances[$name];
     }
+
+    private function isUploadCall(string $path): bool
+    {
+        $path = strtolower($path);
+
+        return (false !== strpos($path, '/uploads.json')) || (false !== strpos($path, '/uploads.xml'));
+    }
+
+    private function isValidFilePath(string $body): bool
+    {
+        return
+            '' !== $body
+            && strlen($body) <= \PHP_MAXPATHLEN
+            && is_file(strval(str_replace("\0", '', $body)))
+        ;
+    }
 }
diff --git a/src/Redmine/Client/NativeCurlClient.php b/src/Redmine/Client/NativeCurlClient.php
index 4553a788..4ef910a1 100644
--- a/src/Redmine/Client/NativeCurlClient.php
+++ b/src/Redmine/Client/NativeCurlClient.php
@@ -271,7 +271,9 @@ private function createCurl(string $method, string $path, string $body = '')
         switch ($method) {
             case 'post':
                 $curlOptions[CURLOPT_POST] = 1;
-                if ($this->isUploadCall($path, $body)) {
+                if ($this->isUploadCall($path) && $this->isValidFilePath($body)) {
+                    @trigger_error('Uploading an attachment by filepath is deprecated, use file_get_contents() to upload the file content instead.', E_USER_DEPRECATED);
+
                     $file = fopen($body, 'r');
                     $size = filesize($body);
                     $filedata = fread($file, $size);
@@ -311,15 +313,6 @@ private function createCurl(string $method, string $path, string $body = '')
         return $curl;
     }
 
-    private function isUploadCall(string $path, string $body): bool
-    {
-        return
-            (preg_match('/\/uploads.(json|xml)/i', $path)) &&
-            '' !== $body &&
-            is_file(strval(str_replace("\0", '', $body)))
-        ;
-    }
-
     private function createHttpHeader(string $path): array
     {
         // Additional request headers
@@ -360,7 +353,7 @@ private function createHttpHeader(string $path): array
         // Content type headers
         $tmp = parse_url($this->url.$path);
 
-        if (preg_match('/\/uploads.(json|xml)/i', $path)) {
+        if ($this->isUploadCall($path)) {
             $httpHeaders[] = 'Content-Type: application/octet-stream';
         } elseif ('json' === substr($tmp['path'], -4)) {
             $httpHeaders[] = 'Content-Type: application/json';
diff --git a/src/Redmine/Client/Psr18Client.php b/src/Redmine/Client/Psr18Client.php
index b7c17509..f67a0a41 100644
--- a/src/Redmine/Client/Psr18Client.php
+++ b/src/Redmine/Client/Psr18Client.php
@@ -181,7 +181,9 @@ private function createRequest(string $method, string $path, string $body = ''):
 
         switch ($method) {
             case 'POST':
-                if ($this->isUploadCall($path, $body)) {
+                if ($this->isUploadCall($path) && $this->isValidFilePath($body)) {
+                    @trigger_error('Uploading an attachment by filepath is deprecated, use file_get_contents() to upload the file content instead.', E_USER_DEPRECATED);
+
                     $request = $request->withBody(
                         $this->streamFactory->createStreamFromFile($body)
                     );
@@ -203,7 +205,7 @@ private function createRequest(string $method, string $path, string $body = ''):
         // set Content-Type header
         $tmp = parse_url($this->url.$path);
 
-        if (preg_match('/\/uploads.(json|xml)/i', $path)) {
+        if ($this->isUploadCall($path)) {
             $request = $request->withHeader('Content-Type', 'application/octet-stream');
         } elseif ('json' === substr($tmp['path'], -4)) {
             $request = $request->withHeader('Content-Type', 'application/json');
@@ -213,13 +215,4 @@ private function createRequest(string $method, string $path, string $body = ''):
 
         return $request;
     }
-
-    private function isUploadCall(string $path, string $body): bool
-    {
-        return
-            (preg_match('/\/uploads.(json|xml)/i', $path)) &&
-            '' !== $body &&
-            is_file(strval(str_replace("\0", '', $body)))
-        ;
-    }
 }