Setting MaxMTU for Windows 95 Dial-Up Networking

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Be warned that this is a complex and tricky procedure that is not for the faint of heart. Be sure to back up your Registry first (e.g., with Microsoft's Configuration Backup Utility and/or Emergency Recovery Utility)! Then run "regedit" and follow these steps:

Find the key "HKEY_LOCAL_MACHINE\Enum\Root\Net. It will have one or more subkeys with names like "0000", "0001", etc. Find and update all entries that have a "DeviceDesc" starting with "Dial-Up Adapter" [e.g., "Dial-Up Adapter" and "Dial-Up Adapter #2 (VPN Support)"]. Within each four-digit subkey there will be a subkey named "Bindings". Within each "Bindings" subkey there will be a string name like "MSTCP\0000". Use the four-digit number(s) after "MSTCP\" in the next step.
Find the key(s) "HKEY_LOCAL_MACHINE\Enum\Network\MSTCP\nnnn" where "nnnn" are replaced by all the four-digit number(s) you found in Step 1 (above). Within those key(s), there will be string(s) named "Driver" with value(s) like "NetTrans\0000". Use the four-digit number(s) after "NetTrans\" in the next step.
Find the key(s) "HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Class\NetTrans\nnnn" where "nnnn" is replaced by all the four-digit number(s) you found in Step 2 (above). Within those key(s), add new string value(s) named "MaxMTU". Then set the value(s) of "MaxMTU" to "576".

Now close "regedit", restart Windows 95, and give it a try.

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