gsharp: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/gsharp - from package: mono-tools-gui

You may install the required package with command apt-get install {package}

Error in other languages:
gsharp: bevel nie gevind nie
gsharp: comandă negăsită
gsharp: comando não encontrado
gsharp: commande introuvable
gsharp: command not found
gsharp: käsku ei ole
gsharp: không tìm thấy lệnh
gsharp: komanda nerasta
gsharp: Kommando nicht gefunden.
gsharp: kommandot finns inte
gsharp: komut yok
gsharp: nie znaleziono polecenia
gsharp: níor aimsíodh an t-ordú
gsharp: no se encontró la orden
gsharp: no s'ha trobat l'ordre
gsharp: opdracht niet gevonden
gsharp: parancs nem található
gsharp: perintah tidak ditemukan
gsharp: príkaz nenájdený
gsharp: příkaz nenalezen
gsharp: команда не найдена
gsharp: командата не е открита
gsharp: 命令找不到
gsharp: コマンドが見つかりません