Character Limitations in File Migration
Understanding filename restrictions and how they're handled during migration to Microsoft 365.
Invalid Characters Automatically Replaced
Overview
Microsoft restricts certain special characters in OneDrive and SharePoint filenames. During migration, Cloudiway automatically handles most character issues by replacing invalid characters with underscores (_) to ensure successful file transfer.
Automatic Handling
Invalid Characters
File and folder names cannot contain these special characters in OneDrive and SharePoint:
Forbidden Characters
Double quote
Asterisk
Colon
Less than
Greater than
Question mark
Forward slash
Backslash
Pipe
These characters are automatically replaced with underscores (_) during migration to create valid filenames in the target environment.
Special Characters (# and %)
The hash (#) and percent (%) characters require special handling:
Important Considerations
Hash character
Requires special configuration to enable. May be translated by default rules.
Percent character
Requires special configuration. Can cause URL encoding issues.
Metadata Limitation
Path Length Restrictions
Microsoft imposes length restrictions on file paths:
| Component | Maximum Length |
|---|---|
| Individual filename or folder | 128 characters |
| Full file URL | 400 characters |
Google Drive has unlimited path lengths, so files migrating from Google may exceed these limits and require special handling.
The zTruncated Folder Solution
When migrating files with paths exceeding 400 characters, Cloudiway uses a special solution to ensure no data is lost:
How It Works
- 1 URLs exceeding 400 characters are automatically detected
- 2 Affected files are placed in a folder named zTruncated at the OneDrive root
- 3 A reference file is created documenting the original file location
Example Structure
OneDrive/
├── Documents/
│ └── Projects/
│ └── ... (normal files)
└── zTruncated/
├── file1.docx
├── file2.xlsx
└── _reference.txt ← Contains original paths Recommendations
Before Migration
- • Audit files with # or % characters
- • Identify deeply nested folder structures
- • Rename files with invalid characters if metadata is important
- • Consider flattening deep hierarchies
After Migration
- • Check the zTruncated folder for relocated files
- • Review the reference file for original locations
- • Manually reorganize files if needed
- • Verify file permissions were transferred correctly