Resolved Map Drive missing within an Application

Hi guys

In a PC1 with win7.HomePremium.sp1 OS (part of LAN), a folder in another PC (say PC2) within the LAN was mapped as "M" or \\PC2\Com. Within PC1, M drive appears in the Network Places and MyComputer as expected.

However within an application running in PC1 that expose drives, "M" does not appear; instead \\PC2\Com appears. This does not happen in other PC in the LAN that has mapped to \\PC2\Com. Puzzle?

I don't think it is Malware as the system is newly reinstalled and well protected.
Moreover a VB6 application that also expose drives, "M" appears.

 

The problem disappeared when i remap the drive ie the Application shows M drive. Why, don't know.