You can fix it like that:
http://support.microsoft.com/kb/926934/en-us
To work around this problem, use one of the following methods:
- Use the CTRL + ALT keyboard shortcut instead of the ALT GR key to type extended characters in the Terminal Services session.
- Configure Windows to stop applying keyboard shortcuts to Terminal Services sessions. To do this, follow these steps:
- Click Start, click Run, type mstsc.exe, and then click OK.
- In the Remote Desktop Connection dialog box, click Options, and then click the Local resources tab.
- In the Apply Windows key combinations list, click On the local computer.
- On the General tab, click Save As, type a name in the File name box, and then click Save.