Take a look how easy it is for PowerShell to create random passwords:
PS > $list = [Char[]]'abcdefgABCDEFG0123456&%$' PS > -join (1..20 | Foreach-Object { Get-Random $list -count 1 }) CbA3egDcgc55a064D50F PS > -join (1..20 | Foreach-Object { Get-Random $list -count 1 }) 406Bf2Fa6GE1a1Fe6Bfa PS > -join (1..20 | Foreach-Object { Get-Random $list -count 1 }) DF%D$EDe1fB4&0B4EDg1
Simply create a list of allowable characters. Next, a loop will randomly pick characters out of that list, and -join will bind them together to a string. You can adjust the list of allowable characters to draw from and then adjust the number of iterations to control the password length.
