diff --git a/docs/content/commands/rclone_mount.md b/docs/content/commands/rclone_mount.md
index f13c5a105..9e387df4e 100644
--- a/docs/content/commands/rclone_mount.md
+++ b/docs/content/commands/rclone_mount.md
@@ -1,5 +1,5 @@
 ---
-date: 2020-02-10T14:40:51Z
+date: 2020-02-10T14:50:44Z
 title: "rclone mount"
 slug: rclone_mount
 url: /commands/rclone_mount/
@@ -316,6 +316,42 @@ This mode should support all normal file system operations.
 If an upload or download fails it will be retried up to
 --low-level-retries times.
 
+### Case Sensitivity
+
+Linux file systems are case-sensitive: two files can differ only
+by case, and the exact case must be used when opening a file.
+
+Windows is not like most other operating systems supported by rclone.
+File systems in modern Windows are case-insensitive but case-preserving:
+although existing files can be opened using any case, the exact case used
+to create the file is preserved and available for programs to query.
+It is not allowed for two files in the same directory to differ only by case.
+
+Usually file systems on MacOS are case-insensitive. It is possible to make MacOS
+file systems case-sensitive but that is not the default
+
+The "--vfs-case-insensitive" mount flag controls how rclone handles these
+two cases. If its value is "false", rclone passes file names to the mounted
+file system as is. If the flag is "true" (or appears without a value on
+command line), rclone may perform a "fixup" as explained below.
+
+The user may specify a file name to open/delete/rename/etc with a case
+different than what is stored on mounted file system. If an argument refers
+to an existing file with exactly the same name, then the case of the existing
+file on the disk will be used. However, if a file name with exactly the same
+name is not found but a name differing only by case exists, rclone will
+transparently fixup the name. This fixup happens only when an existing file
+is requested. Case sensitivity of file names created anew by rclone is
+controlled by an underlying mounted file system.
+
+Note that case sensitivity of the operating system running rclone (the target)
+may differ from case sensitivity of a file system mounted by rclone (the source).
+The flag controls whether "fixup" is performed to satisfy the target.
+
+If the flag is not provided on command line, then its default value depends
+on the operating system where rclone runs: "true" on Windows and MacOS, "false"
+otherwise. If the flag is provided without a value, then it is "true".
+
 
 ```
 rclone mount remote:path /path/to/mountpoint [flags]
diff --git a/docs/content/commands/rclone_serve_dlna.md b/docs/content/commands/rclone_serve_dlna.md
index 93af95b67..1623ad758 100644
--- a/docs/content/commands/rclone_serve_dlna.md
+++ b/docs/content/commands/rclone_serve_dlna.md
@@ -1,5 +1,5 @@
 ---
-date: 2020-02-10T12:28:36Z
+date: 2020-02-10T14:50:44Z
 title: "rclone serve dlna"
 slug: rclone_serve_dlna
 url: /commands/rclone_serve_dlna/
@@ -167,6 +167,42 @@ This mode should support all normal file system operations.
 If an upload or download fails it will be retried up to
 --low-level-retries times.
 
+### Case Sensitivity
+
+Linux file systems are case-sensitive: two files can differ only
+by case, and the exact case must be used when opening a file.
+
+Windows is not like most other operating systems supported by rclone.
+File systems in modern Windows are case-insensitive but case-preserving:
+although existing files can be opened using any case, the exact case used
+to create the file is preserved and available for programs to query.
+It is not allowed for two files in the same directory to differ only by case.
+
+Usually file systems on MacOS are case-insensitive. It is possible to make MacOS
+file systems case-sensitive but that is not the default
+
+The "--vfs-case-insensitive" mount flag controls how rclone handles these
+two cases. If its value is "false", rclone passes file names to the mounted
+file system as is. If the flag is "true" (or appears without a value on
+command line), rclone may perform a "fixup" as explained below.
+
+The user may specify a file name to open/delete/rename/etc with a case
+different than what is stored on mounted file system. If an argument refers
+to an existing file with exactly the same name, then the case of the existing
+file on the disk will be used. However, if a file name with exactly the same
+name is not found but a name differing only by case exists, rclone will
+transparently fixup the name. This fixup happens only when an existing file
+is requested. Case sensitivity of file names created anew by rclone is
+controlled by an underlying mounted file system.
+
+Note that case sensitivity of the operating system running rclone (the target)
+may differ from case sensitivity of a file system mounted by rclone (the source).
+The flag controls whether "fixup" is performed to satisfy the target.
+
+If the flag is not provided on command line, then its default value depends
+on the operating system where rclone runs: "true" on Windows and MacOS, "false"
+otherwise. If the flag is provided without a value, then it is "true".
+
 
 ```
 rclone serve dlna remote:path [flags]
diff --git a/docs/content/commands/rclone_serve_ftp.md b/docs/content/commands/rclone_serve_ftp.md
index d07cf0308..c5440efaa 100644
--- a/docs/content/commands/rclone_serve_ftp.md
+++ b/docs/content/commands/rclone_serve_ftp.md
@@ -1,5 +1,5 @@
 ---
-date: 2020-02-10T14:24:31Z
+date: 2020-02-10T14:50:44Z
 title: "rclone serve ftp"
 slug: rclone_serve_ftp
 url: /commands/rclone_serve_ftp/
@@ -166,6 +166,42 @@ This mode should support all normal file system operations.
 If an upload or download fails it will be retried up to
 --low-level-retries times.
 
+### Case Sensitivity
+
+Linux file systems are case-sensitive: two files can differ only
+by case, and the exact case must be used when opening a file.
+
+Windows is not like most other operating systems supported by rclone.
+File systems in modern Windows are case-insensitive but case-preserving:
+although existing files can be opened using any case, the exact case used
+to create the file is preserved and available for programs to query.
+It is not allowed for two files in the same directory to differ only by case.
+
+Usually file systems on MacOS are case-insensitive. It is possible to make MacOS
+file systems case-sensitive but that is not the default
+
+The "--vfs-case-insensitive" mount flag controls how rclone handles these
+two cases. If its value is "false", rclone passes file names to the mounted
+file system as is. If the flag is "true" (or appears without a value on
+command line), rclone may perform a "fixup" as explained below.
+
+The user may specify a file name to open/delete/rename/etc with a case
+different than what is stored on mounted file system. If an argument refers
+to an existing file with exactly the same name, then the case of the existing
+file on the disk will be used. However, if a file name with exactly the same
+name is not found but a name differing only by case exists, rclone will
+transparently fixup the name. This fixup happens only when an existing file
+is requested. Case sensitivity of file names created anew by rclone is
+controlled by an underlying mounted file system.
+
+Note that case sensitivity of the operating system running rclone (the target)
+may differ from case sensitivity of a file system mounted by rclone (the source).
+The flag controls whether "fixup" is performed to satisfy the target.
+
+If the flag is not provided on command line, then its default value depends
+on the operating system where rclone runs: "true" on Windows and MacOS, "false"
+otherwise. If the flag is provided without a value, then it is "true".
+
 ### Auth Proxy
 
 If you supply the parameter `--auth-proxy /path/to/program` then
diff --git a/docs/content/commands/rclone_serve_http.md b/docs/content/commands/rclone_serve_http.md
index ccd182b50..5b0715e30 100644
--- a/docs/content/commands/rclone_serve_http.md
+++ b/docs/content/commands/rclone_serve_http.md
@@ -1,5 +1,5 @@
 ---
-date: 2020-02-10T12:28:36Z
+date: 2020-02-10T14:50:44Z
 title: "rclone serve http"
 slug: rclone_serve_http
 url: /commands/rclone_serve_http/
@@ -215,6 +215,42 @@ This mode should support all normal file system operations.
 If an upload or download fails it will be retried up to
 --low-level-retries times.
 
+### Case Sensitivity
+
+Linux file systems are case-sensitive: two files can differ only
+by case, and the exact case must be used when opening a file.
+
+Windows is not like most other operating systems supported by rclone.
+File systems in modern Windows are case-insensitive but case-preserving:
+although existing files can be opened using any case, the exact case used
+to create the file is preserved and available for programs to query.
+It is not allowed for two files in the same directory to differ only by case.
+
+Usually file systems on MacOS are case-insensitive. It is possible to make MacOS
+file systems case-sensitive but that is not the default
+
+The "--vfs-case-insensitive" mount flag controls how rclone handles these
+two cases. If its value is "false", rclone passes file names to the mounted
+file system as is. If the flag is "true" (or appears without a value on
+command line), rclone may perform a "fixup" as explained below.
+
+The user may specify a file name to open/delete/rename/etc with a case
+different than what is stored on mounted file system. If an argument refers
+to an existing file with exactly the same name, then the case of the existing
+file on the disk will be used. However, if a file name with exactly the same
+name is not found but a name differing only by case exists, rclone will
+transparently fixup the name. This fixup happens only when an existing file
+is requested. Case sensitivity of file names created anew by rclone is
+controlled by an underlying mounted file system.
+
+Note that case sensitivity of the operating system running rclone (the target)
+may differ from case sensitivity of a file system mounted by rclone (the source).
+The flag controls whether "fixup" is performed to satisfy the target.
+
+If the flag is not provided on command line, then its default value depends
+on the operating system where rclone runs: "true" on Windows and MacOS, "false"
+otherwise. If the flag is provided without a value, then it is "true".
+
 
 ```
 rclone serve http remote:path [flags]
diff --git a/docs/content/commands/rclone_serve_sftp.md b/docs/content/commands/rclone_serve_sftp.md
index 1265e36a5..c622b6fc1 100644
--- a/docs/content/commands/rclone_serve_sftp.md
+++ b/docs/content/commands/rclone_serve_sftp.md
@@ -1,5 +1,5 @@
 ---
-date: 2020-02-10T14:24:31Z
+date: 2020-02-10T14:50:44Z
 title: "rclone serve sftp"
 slug: rclone_serve_sftp
 url: /commands/rclone_serve_sftp/
@@ -177,6 +177,42 @@ This mode should support all normal file system operations.
 If an upload or download fails it will be retried up to
 --low-level-retries times.
 
+### Case Sensitivity
+
+Linux file systems are case-sensitive: two files can differ only
+by case, and the exact case must be used when opening a file.
+
+Windows is not like most other operating systems supported by rclone.
+File systems in modern Windows are case-insensitive but case-preserving:
+although existing files can be opened using any case, the exact case used
+to create the file is preserved and available for programs to query.
+It is not allowed for two files in the same directory to differ only by case.
+
+Usually file systems on MacOS are case-insensitive. It is possible to make MacOS
+file systems case-sensitive but that is not the default
+
+The "--vfs-case-insensitive" mount flag controls how rclone handles these
+two cases. If its value is "false", rclone passes file names to the mounted
+file system as is. If the flag is "true" (or appears without a value on
+command line), rclone may perform a "fixup" as explained below.
+
+The user may specify a file name to open/delete/rename/etc with a case
+different than what is stored on mounted file system. If an argument refers
+to an existing file with exactly the same name, then the case of the existing
+file on the disk will be used. However, if a file name with exactly the same
+name is not found but a name differing only by case exists, rclone will
+transparently fixup the name. This fixup happens only when an existing file
+is requested. Case sensitivity of file names created anew by rclone is
+controlled by an underlying mounted file system.
+
+Note that case sensitivity of the operating system running rclone (the target)
+may differ from case sensitivity of a file system mounted by rclone (the source).
+The flag controls whether "fixup" is performed to satisfy the target.
+
+If the flag is not provided on command line, then its default value depends
+on the operating system where rclone runs: "true" on Windows and MacOS, "false"
+otherwise. If the flag is provided without a value, then it is "true".
+
 ### Auth Proxy
 
 If you supply the parameter `--auth-proxy /path/to/program` then
diff --git a/docs/content/commands/rclone_serve_webdav.md b/docs/content/commands/rclone_serve_webdav.md
index 10114f219..4d68f4744 100644
--- a/docs/content/commands/rclone_serve_webdav.md
+++ b/docs/content/commands/rclone_serve_webdav.md
@@ -1,5 +1,5 @@
 ---
-date: 2020-02-10T14:24:31Z
+date: 2020-02-10T14:50:44Z
 title: "rclone serve webdav"
 slug: rclone_serve_webdav
 url: /commands/rclone_serve_webdav/
@@ -223,6 +223,42 @@ This mode should support all normal file system operations.
 If an upload or download fails it will be retried up to
 --low-level-retries times.
 
+### Case Sensitivity
+
+Linux file systems are case-sensitive: two files can differ only
+by case, and the exact case must be used when opening a file.
+
+Windows is not like most other operating systems supported by rclone.
+File systems in modern Windows are case-insensitive but case-preserving:
+although existing files can be opened using any case, the exact case used
+to create the file is preserved and available for programs to query.
+It is not allowed for two files in the same directory to differ only by case.
+
+Usually file systems on MacOS are case-insensitive. It is possible to make MacOS
+file systems case-sensitive but that is not the default
+
+The "--vfs-case-insensitive" mount flag controls how rclone handles these
+two cases. If its value is "false", rclone passes file names to the mounted
+file system as is. If the flag is "true" (or appears without a value on
+command line), rclone may perform a "fixup" as explained below.
+
+The user may specify a file name to open/delete/rename/etc with a case
+different than what is stored on mounted file system. If an argument refers
+to an existing file with exactly the same name, then the case of the existing
+file on the disk will be used. However, if a file name with exactly the same
+name is not found but a name differing only by case exists, rclone will
+transparently fixup the name. This fixup happens only when an existing file
+is requested. Case sensitivity of file names created anew by rclone is
+controlled by an underlying mounted file system.
+
+Note that case sensitivity of the operating system running rclone (the target)
+may differ from case sensitivity of a file system mounted by rclone (the source).
+The flag controls whether "fixup" is performed to satisfy the target.
+
+If the flag is not provided on command line, then its default value depends
+on the operating system where rclone runs: "true" on Windows and MacOS, "false"
+otherwise. If the flag is provided without a value, then it is "true".
+
 ### Auth Proxy
 
 If you supply the parameter `--auth-proxy /path/to/program` then
diff --git a/vfs/help.go b/vfs/help.go
index 180965aa3..3e5704e60 100644
--- a/vfs/help.go
+++ b/vfs/help.go
@@ -136,4 +136,40 @@ This mode should support all normal file system operations.
 
 If an upload or download fails it will be retried up to
 --low-level-retries times.
+
+### Case Sensitivity
+
+Linux file systems are case-sensitive: two files can differ only
+by case, and the exact case must be used when opening a file.
+
+Windows is not like most other operating systems supported by rclone.
+File systems in modern Windows are case-insensitive but case-preserving:
+although existing files can be opened using any case, the exact case used
+to create the file is preserved and available for programs to query.
+It is not allowed for two files in the same directory to differ only by case.
+
+Usually file systems on MacOS are case-insensitive. It is possible to make MacOS
+file systems case-sensitive but that is not the default
+
+The "--vfs-case-insensitive" mount flag controls how rclone handles these
+two cases. If its value is "false", rclone passes file names to the mounted
+file system as is. If the flag is "true" (or appears without a value on
+command line), rclone may perform a "fixup" as explained below.
+
+The user may specify a file name to open/delete/rename/etc with a case
+different than what is stored on mounted file system. If an argument refers
+to an existing file with exactly the same name, then the case of the existing
+file on the disk will be used. However, if a file name with exactly the same
+name is not found but a name differing only by case exists, rclone will
+transparently fixup the name. This fixup happens only when an existing file
+is requested. Case sensitivity of file names created anew by rclone is
+controlled by an underlying mounted file system.
+
+Note that case sensitivity of the operating system running rclone (the target)
+may differ from case sensitivity of a file system mounted by rclone (the source).
+The flag controls whether "fixup" is performed to satisfy the target.
+
+If the flag is not provided on command line, then its default value depends
+on the operating system where rclone runs: "true" on Windows and MacOS, "false"
+otherwise. If the flag is provided without a value, then it is "true".
 `