isql call unable to open input file

I am making a call with Sybase isql. It works from a standard command prompt but fails in Powershell. The SQL file is a simple "select count" for now.

Command Prompt:

H:\>isql -SSomeServer -USomeUser -PSomePassword -DSomeDatabase -i\\path\to\sql\file\SomeFile.sql

 -----------
       81210

(1 row affected)

Powershell:

PS H:\> isql -SSomeServer -USomeUser -PSomePassword -DSomeDatabase -i\\path\to\sql\file\SomeFile.sql
Unable to open input file '\\path\to\sql\file\SomeFile'.

I have tried putting single and double quotes around the file, but that results in a continued prompt (>>).

Thank you,

Shawn