diff --git a/cmd/errors.go b/cmd/errors.go
index 00e20b8..807ae8d 100644
--- a/cmd/errors.go
+++ b/cmd/errors.go
@@ -16,11 +16,11 @@ import (
 )
 
 var (
-	ErrInvalidAdminPrefix    = errors.New("admin path must not contain a '/'")
+	ErrInvalidAdminPrefix    = errors.New("admin path must match the pattern " + AllowedCharacters)
 	ErrInvalidConcurrency    = errors.New("concurrency limit must be between 1 and 8192 inclusive")
 	ErrInvalidFileCountRange = errors.New("maximum file count limit must be greater than or equal to minimum file count limit")
 	ErrInvalidFileCountValue = errors.New("file count limits must be non-negative integers no greater than 2147483647")
-	ErrInvalidIgnoreFile     = errors.New("ignore filename must match the pattern " + ignoreFilePattern)
+	ErrInvalidIgnoreFile     = errors.New("ignore filename must match the pattern " + AllowedCharacters)
 	ErrInvalidPort           = errors.New("listen port must be an integer between 1 and 65535 inclusive")
 	ErrNoMediaFound          = errors.New("no supported media formats found which match all criteria")
 )
diff --git a/cmd/files.go b/cmd/files.go
index d7b0c2f..55f69da 100644
--- a/cmd/files.go
+++ b/cmd/files.go
@@ -22,8 +22,6 @@ import (
 	"seedno.de/seednode/roulette/types"
 )
 
-const ignoreFilePattern string = `^[A-z0-9.\-_]+$`
-
 type regexes struct {
 	alphanumeric *regexp.Regexp
 	filename     *regexp.Regexp
diff --git a/cmd/root.go b/cmd/root.go
index 2aaef1e..fa3ff33 100644
--- a/cmd/root.go
+++ b/cmd/root.go
@@ -8,13 +8,13 @@ import (
 	"log"
 	"math"
 	"regexp"
-	"strings"
 
 	"github.com/spf13/cobra"
 )
 
 const (
-	ReleaseVersion string = "3.5.2"
+	AllowedCharacters string = `^[A-z0-9.\-_]+$`
+	ReleaseVersion    string = "3.5.3"
 )
 
 var (
@@ -79,9 +79,9 @@ var (
 				return ErrInvalidPort
 			case Concurrency < 1 || Concurrency > 8192:
 				return ErrInvalidConcurrency
-			case Ignore && !regexp.MustCompile(ignoreFilePattern).MatchString(IgnoreFile):
+			case Ignore && !regexp.MustCompile(AllowedCharacters).MatchString(IgnoreFile):
 				return ErrInvalidIgnoreFile
-			case strings.Contains(AdminPrefix, "/"):
+			case AdminPrefix != "" && !regexp.MustCompile(AllowedCharacters).MatchString(AdminPrefix):
 				return ErrInvalidAdminPrefix
 			case AdminPrefix != "":
 				AdminPrefix = "/" + AdminPrefix