diff --git a/crates/cargo-test-support/src/lib.rs b/crates/cargo-test-support/src/lib.rs
index d1a76f312..d18fa5dda 100644
--- a/crates/cargo-test-support/src/lib.rs
+++ b/crates/cargo-test-support/src/lib.rs
@@ -1846,3 +1846,12 @@ pub fn symlink_supported() -> bool {
 pub fn symlink_supported() -> bool {
     true
 }
+
+/// The error message for ENOENT.
+///
+/// It's generally not good to match against OS error messages, but I think
+/// this one is relatively stable.
+#[cfg(windows)]
+pub const NO_SUCH_FILE_ERR_MSG: &str = "The system cannot find the file specified. (os error 2)";
+#[cfg(not(windows))]
+pub const NO_SUCH_FILE_ERR_MSG: &str = "No such file or directory (os error 2)";
diff --git a/tests/testsuite/advanced_env.rs b/tests/testsuite/advanced_env.rs
index 21e6a6f98..64d02809f 100644
--- a/tests/testsuite/advanced_env.rs
+++ b/tests/testsuite/advanced_env.rs
@@ -3,6 +3,9 @@
 use cargo_test_support::{paths, project, registry::Package};
 
 #[cargo_test]
+// I don't know why, but `Command` forces all env keys to be upper case on
+// Windows. Seems questionable, since I think Windows is case-preserving.
+#[cfg_attr(windows, ignore)]
 fn source_config_env() {
     // Try to define [source] with environment variables.
     let p = project()
diff --git a/tests/testsuite/config_include.rs b/tests/testsuite/config_include.rs
index 7f3aea692..1daec8bce 100644
--- a/tests/testsuite/config_include.rs
+++ b/tests/testsuite/config_include.rs
@@ -3,6 +3,7 @@
 use super::config::{
     assert_error, assert_match, read_output, write_config, write_config_at, ConfigBuilder,
 };
+use cargo_test_support::NO_SUCH_FILE_ERR_MSG;
 
 #[cargo_test]
 fn gated() {
@@ -78,7 +79,8 @@ fn missing_file() {
     let config = ConfigBuilder::new().unstable_flag("config-include").build();
     assert_error(
         config.get::<i32>("whatever").unwrap_err(),
-        "\
+        &format!(
+            "\
 could not load Cargo configuration
 
 Caused by:
@@ -88,7 +90,9 @@ Caused by:
   failed to read configuration file `[..]/.cargo/missing`
 
 Caused by:
-  No such file or directory (os error 2)",
+  {}",
+            NO_SUCH_FILE_ERR_MSG
+        ),
     );
 }
 
@@ -162,11 +166,14 @@ fn cli_include_failed() {
         .build_err();
     assert_error(
         config.unwrap_err(),
-        "\
+        &format!(
+            "\
 failed to load --config include
 failed to load config include `foobar` from `--config cli option`
 failed to read configuration file `[..]/foobar`
-No such file or directory (os error 2)",
+{}",
+            NO_SUCH_FILE_ERR_MSG
+        ),
     );
 }
 
diff --git a/tests/testsuite/install.rs b/tests/testsuite/install.rs
index 3df720a9d..98dd12fe2 100644
--- a/tests/testsuite/install.rs
+++ b/tests/testsuite/install.rs
@@ -12,7 +12,7 @@ use cargo_test_support::install::{
 };
 use cargo_test_support::paths;
 use cargo_test_support::registry::Package;
-use cargo_test_support::{basic_manifest, cargo_process, project};
+use cargo_test_support::{basic_manifest, cargo_process, project, NO_SUCH_FILE_ERR_MSG};
 
 fn pkg(name: &str, vers: &str) {
     Package::new(name, vers)
@@ -824,11 +824,6 @@ fn uninstall_cwd_not_installed() {
 
 #[cargo_test]
 fn uninstall_cwd_no_project() {
-    let err_msg = if cfg!(windows) {
-        "The system cannot find the file specified."
-    } else {
-        "No such file or directory"
-    };
     cargo_process("uninstall")
         .with_status(101)
         .with_stdout("")
@@ -837,8 +832,8 @@ fn uninstall_cwd_no_project() {
 [ERROR] failed to read `[CWD]/Cargo.toml`
 
 Caused by:
-  {err_msg} (os error 2)",
-            err_msg = err_msg,
+  {err_msg}",
+            err_msg = NO_SUCH_FILE_ERR_MSG,
         ))
         .run();
 }
diff --git a/tests/testsuite/tool_paths.rs b/tests/testsuite/tool_paths.rs
index 7d9a5b905..8d13000ef 100644
--- a/tests/testsuite/tool_paths.rs
+++ b/tests/testsuite/tool_paths.rs
@@ -279,7 +279,7 @@ fn custom_runner_env() {
     p.cargo("run")
         .env(&key, "nonexistent-runner --foo")
         .with_status(101)
-        .with_stderr_contains("[RUNNING] `nonexistent-runner --foo target/debug/foo`")
+        .with_stderr_contains("[RUNNING] `nonexistent-runner --foo target/debug/foo[EXE]`")
         .run();
 }