Yes, there is a limit on the number of characters allowed for a GRID path on Windows platforms.
GRID paths longer than 120 characters (including the name of a GRID) return an error message when a value attribute table (VAT) of a GRID is edited.
For example, when trying to add a new field to a GRID that has a path longer than 120 characters, the following error message is returned:
“Failed to add the field to the table/feature class”.
Likewise, deleting an existing field from a GRID that has a path longer than 120 characters returns the following error message:
“Failed to delete selected field”.
It is important to note this even in a geoprocessing environment if editing is being done on GRID tables (VAT).
Refer to the article in Related Information for information about path names' limits on GRIDs in UNIX environments.