I use my own software to manage my emails

When I save attachments I use the file name I get from the server to name the file to be saved

But sometimes the file name has weird caracters as below,
and it results in error when saving the file

 file2001abc5%9#<ƒ-@ ŠÊ<óŸumo]@.jpg

Is there anyway to remove all strange chars and keep only a-z and 0-1 chars ?

I tried CHRTRAN( ) but it's impossible to predict what strange char I will receive

I dont need to replace the weird char, just delete it

Moises