I'm getting this message below, and I'm not sure what is causing the issue because I have another string that starts with "[UserColor]" and "[MembersOf-17]", both of which also have a "[", and it works fine.
The regular expression pattern [MembersOf-7] is not valid.
At \\hqfs1\Users\tantony\PowerShell\CalenderGroup\Calender.ps1:156 char:14
+ $Read_INI = $Read_INI -replace("$Items","$Replace")
+ CategoryInfo : InvalidOperation: ([MembersOf-7]:String) , RuntimeException
+ FullyQualifiedErrorId : InvalidRegularExpression